Definition of period in English:

period

noun ˈpɪərɪədˈpɪriəd

1A length or portion of time.
（一段）时间，时期，阶段
he had long periods of depression
他几次陷入长时间的消沉。
the period 1977–85
1977-1985年这一时期。
the training period is between 16 and 18 months
训练期是16到18个月。
Example sentencesExamples
- The fluvial sediments, however, represent rapid deposition in relatively short periods (days or months).
- They are born in relatively short periods after long periods of social disintegration.
- Generally, consumers have accepted the relatively short periods of 14 to 21 days for half or full gallons of milk.
- She hadn't left Hong Kong during the two-week incubation period, it said.
- One of the most enjoyable events in Bolivia is Carnival, the period preceding Lent.
- The prediction is based on the crimes committed so far in the period under review.
- They extend the grace period for the repayment of the loan till March 2006.
- After all, a new president enjoys a honeymoon period of three months at most.
- It is fascinating to relate aerial photographs to maps of all periods, especially on the coast where continuous erosion and deposits often show extravagant change over relatively short periods of time.
- Both males and females undergo periods of inactivity from November until March.
- Unlike here, there has been a significant increase in supply following the long period of inactivity.
- The file dates span the period between September 1996 and April 1997.
- Hopefully, the pertinent questions will be asked after the initial period of mourning.
- Benefits are usually offered after a six-month probationary period and backdated to the start of employment.
- The 1980s were a hectic period in his personal life.
- These results show that spectacular gains may be made in relatively short periods from what may have seemed the least likely candidates.
- A military judge can extend the period of detention incommunicado up to 90 days.
- On release from prison he will have to serve an extended two-year period on licence.
- The survey covered the one-year period ending November, 2003.
- Hauling and applying manure may require large blocks of time for relatively short periods throughout the year.
Synonyms
time, spell, interval, stretch, term, span, phase, session, bout, run, space, duration, chapter, stage
while
British informal patch
1. 1.1 A portion of time in the life of a nation, civilization, etc. characterized by the same prevalent features or conditions.
  阶段；时代
  the early medieval period
  中世纪的早期。
  Example sentencesExamples
  Also featured will be works from the Byzantine, Medieval, and Renaissance periods, as well as late 18th and early 19th century art.
  The art forms that emerged in the early period of civilisation are primitive and catered to a people who had no alternative.
  If we confine ourselves to Europe in the late medieval and early modern periods, we find that at least initial studies have been completed on England, France, Amsterdam, and parts of Germany.
  Life at the bottom of society was always difficult in the late medieval and early modern periods: but around 1600 conditions for many of the poor were terrible.
  The early 1990s also was a period of persistently sluggish growth - in credit, employment and GDP.
  The late 1950s and early 1960s were a period of expansion and creativity.
  Of these, 98 per cent cover the 19th and 20th centuries, while only 16 per cent cover medieval or earlier periods.
  This strong connection between politics and music is a feature of the period.
  In these, information about the history of the regions and archaeological discoveries bring the Viking and early medieval periods to life.
  The nineteenth century was a period of unparalleled imperial expansion.
  Magical beliefs and practices existed at all social levels in the medieval and early modern periods, and were enmeshed in medical and scientific thought and techniques.
  You said we entered a dark period in American history.
  To be sure, the public prayer forms of the West needed culling and refining by the late medieval and early Renaissance periods.
  Nevertheless, the eighteenth century was a period of rapid urban growth.
  We have entered a critical period in financial history.
  The life that one sacrificed to God or king in the medieval and early modern periods became, with the advent of modernity, a life offered in the name of one's country.
  The Book of Kells is one of the great masterpieces that has come down to us from a period often referred to as the Dark Ages.
  Yet the 1990s was a very robust period of growth.
  His work has focused on the medieval and early modern periods.
  Economists and historians regard a reduction in real wages as one of the distinguishing features of the modern period.
  Synonyms
  era, age, epoch, time, days, years, aeon
  generation, date
2. 1.2 A major division of geological time that is a subdivision of an era and is itself subdivided into epochs.
  （地质年代划分的）纪
  the Cretaceous period
  Example sentencesExamples
  The following table shows the three eras and eleven geological periods that comprise the Phanerozoic.
  The event, known as the Great Dying, occurred about 250 million years ago at the boundary between the Permian and Triassic periods.
  Despite our lack of knowledge, or perhaps because of it, researchers have divided the Precambrian into three time periods called eons.
  Later geological periods show similar patterns of sudden appearance, stasis and persistent chasms of difference between major groups.
  This was accompanied by the multistage emplacement of large intrusive bodies in the Cambrian, Ordovician, and Silurian periods.
  Because of this, clay becomes progressively less common in older geological periods and is almost never found in Precambrian formations.
  In contrast, dinosaur fossils have been traced in Triassic, Jurassic and Cretaceous periods.
  Historically, the Cenozoic has been divided up into the Quaternary and Tertiary sub-eras, as well as the Neogene and Paleogene periods.
  This book shows the dynamic effects of the many periods of Pleistocene glacial advance and melting on the geology and topography of the northwestern United States.
  Because the Miocene is closer to the present day than most other periods of geologic time, it is easier to see the effects of events, and to interpret patterns.
  Evolutionists say these formations represent three different geological periods ranging from 35 to 245 million years.
  The extinction occurred at the boundary between the Permian and Triassic periods at a time when all land was concentrated in a supercontinent called Pangea.
  Geological periods are defined with reference to a Global Boundary Stratotype Section and Point.
  The Mesozoic era lasted from about 251 to 66 million years ago and includes the Triassic, Jurassic, and Cretaceous periods.
  During the Cretaceous and the Tertiary periods large parts of the present subcontinent of India were flooded by multiple lava flows.
  The right-hand column lists the six major epochs into which the periods are divided.
  Extinctions have also occurred in all other periods of geological time.
  The Great Dying occurred between the Permian and Triassic periods, when all of today's continents were concentrated in one great land mass called Pangea.
  Most are restricted to one or two geologic periods, and a few contain only one genus.
  We have additional information on the geological time periods along the top of the image.
3. 1.3 Each of the set divisions of the day in a school allocated to a lesson or other activity.
  学时，课时
  two periods of PE are allocated on the timetable
  he interviewed the teachers when they had a free period
  Example sentencesExamples
  Walking down the hallway towards first period trigonometry Jordan smiled as she passed people.
  Teachers should also be in classrooms for all the periods allocated to them and those who served as councillors should be filled in for, he said.
  I would look at it later and make sense of it but, as for now, I had to get to my next lesson because the free period would probably be nearing an end.
  Despite the fact that this lesson took several class periods to complete, I feel it was definitely worth it.
  Dumping her test into the inbox she left the classroom for fourth period Health.
  Even the teacher was very interested in the argument, so she gave the class a free period.
  By the time I got to class, the first period bell was ringing.
  Youngsters coming out of school during free periods were also blamed for trouble in the town.
  When I was looking for my third period class which is Health, the halls were really crowded.
  The two of them reached the door to their first period study hall room.
  I never really got why lessons were called periods.
  My parents were a bit worried when they saw all the free periods in my timetable.
  Uh, you really need to take this up next period in your Comparative Religion class.
  James had a free for periods five and six, so he was in the IT room, out of the cold.
  Nothing could bring him down… until he reached his third period Algebra class.
  In my day, that meant the four boys who drank it in an alley near school during free periods (I joined them once and will spare you the details).
  Most of my teachers were unaware of my hours of research in the school library; the reason for this was that I was supposed to be doing something else in my free periods, so I kept quiet about what I was doing.
  I took a seat in the middle near the window in my fourth period class which was art.
  To accommodate the rich level of activity hoped for in his mathematical laboratory, he proposed that two consecutive class periods be allocated to it.
  The total lesson takes several class periods and I recite the poems to motivate my young artists many times throughout the lesson.
  Synonyms
  lesson, class, session
4. 1.4 Each of the divisions of the playing time of a sporting event.
  （体育比赛的）局
  the Lightnings ran at the Leafs hard in a very rough first period
  Example sentencesExamples
  Between periods in the locker rooms, IVs drip fluids into dehydrated athletes, who eat bananas and drink even more liquids to fight off cramping.
  He also missed a 30m penalty in the first period of extra time.
  Kinsale scored the decisive second goal three minutes into the first period of extra-time.
  But, once he scored in the sixth minute of the injury time, the script for the extra time periods could have been written.
  If games are tied at full-time an extra period will be played with the first team to score winning the game.
  There is an extra period called injury time, usually in the vicinity of three minutes.
  A tense period of extra-time failed to produce a winning goal for either team.
  Why is a penalty in the first period of a game in December not a penalty in the third period of a game in March?
  However, with almost the last kick of the game, he scored the winning point in the fourth period of extra time.
  The second period of extra time saw the home side get a goal back.
  His save percentage and GAA in the third period is better than in the first two periods.
  Venezuela was reduced to ten players for the second period of extra time and the pressure shifted to Uruguay.
  They turned into gaping holes in the final period when three Belfast goals in as many minutes ended the contest.
  Teams play full periods with no TV timeouts - the ultimate test of conditioning.
  In the first period of extra time both teams played at a frenetic pace with tenacious defending keeping Keighley's hopes alive.
  There were no goals in the first period of extra time but within a minute of the restart a through-ball fell to Bowers, who made no mistake.
  In the second period of extra time United pushed hard looking again for another equaliser.
  They totally dominated the first period, scoring five and conceding one.
  The match ended scoreless in normal time, but the team conceded a goal in the first period of extra time.
  There have been 17 periods of extra time in European Championships and World Cups since the Golden Goal system began at Euro 96.
2Physics
The interval of time between successive occurrences of the same state in an oscillatory or cyclic phenomenon, such as a mechanical vibration, an alternating current, a variable star, or an electromagnetic wave.
〔物理〕（振动或循环的）周期
Example sentencesExamples
- To produce a larger effect, the motion must accumulate, and for wave-impulses to accumulate, they must arrive in periods identical with the periods of vibration of the atoms on which they impinge.
1. 2.1Astronomy The time taken by a celestial object to rotate about its axis, or to make one circuit of its orbit.
  〔天文〕自转（或公转）周期
  Example sentencesExamples
  Certainly the book would be more compelling if it contained a success story on a par with accounting for the periods of the planetary orbits or the perihelion shift of Mercury.
  In contrast, Jupiter-family comets tend to have predictable, well-determined orbits with short periods and low inclinations.
  Typical distances from the Sun are 10,000 astronomical units, and typical orbital periods are on the order of 1 million years.
  The atmosphere rotates with periods ranging from over 18 hours near the equator to faster than 13 hours near the poles.
  The first problem Galileo attacked at Florence was to determine orbits and periods for Jupiter's four satellites.
2. 2.2Mathematics The interval between successive equal values of a periodic function.
  〔数〕（周期函数的）周期
  Example sentencesExamples
  In 1834 Jacobi proved that if a single-valued function of one variable is doubly periodic then the ratio of the periods is imaginary.
  What is the period of the continued fractions of the following numbers?
3A flow of blood and other material from the lining of the uterus, lasting for a few days and occurring in sexually mature women who are not pregnant at intervals of about one lunar month until the menopause.
（妇女的）经期
she's got her period
as modifier period pains
Example sentencesExamples
- Examples include when a partner leaves, pregnancies among very young women, those with irregular periods or at the menopause, or when testing has shown a baby with abnormalities.
- Many women don't suspect they're pregnant until their period doesn't arrive.
- During early pregnancy, some women develop acne, especially those who were prone to breakouts during menstrual periods before becoming pregnant.
- It mostly affects women between the ages of 50 and 70, who have been through the menopause (when your periods stop).
- Because sex during menstruation may increase the chances of transmitting or contracting HIV, it may be safer for women to wait until their periods are over to have sex.
- If a woman does not have periods (due to menopause or removal of uterus), then it may be done on a fixed day of the month.
- During puberty or nearing menopause, many women have irregular periods so no treatment is necessary.
- About 60% of women who say they have heavy periods are found to have normal periods when their blood loss is measured.
- It affects women much more often than men, because women lose some blood in each menstrual period between puberty and the menopause.
- Women may also experience painful periods and pain during sexual intercourse.
- Most women have some crampy pain with their periods, especially as teenagers.
- Some older women think the absence of periods is related to menopause and not pregnancy.
- Sometimes the cause is clear, for example in women who are pregnant or have heavy periods.
- A headache diary may be necessary to confirm the relationship between migraine and menstruation, especially if periods are irregular.
- Amenorrhea just means an absence of menstrual cycles or periods for at least about three to six months, and the particular type of amenorrhea that we were studying is called hypothalamic.
- You then need to use progesterone pessaries until your periods start again.
- Women who receive chemotherapy may have a change in their periods or menstrual cycles.
- Three standard gynecological texts state that the commonly observed interval between menstrual periods is 26 to 30 days, 24 to 32 days, and 24 to 35 days.
- Amenorrhoea is the absence of periods (menstruation).
- It is common to have heavy blood flow at the beginning of a period and lighter blood flow at the end.
Synonyms
menstruation, menstrual flow
informal the curse, monthlies, time of the month
technical menses
archaic time
rare flowers
4North American A punctuation mark (.) used at the end of a sentence or an abbreviation; a full stop.
Example sentencesExamples
- The dominant American style is to include commas and periods within quotation marks even when that punctuation doesn't belong to the quotation.
- As he talked he jabbed the lit end of his cigar into the air as though he were punctuating his sentences by burning periods in the air.
- He put a period on the end of the last sentence, and placed the pen down with a loud sound and looked up at her.
- The first sentence should have been ended with a period and not a question mark.
- Simple input issues such as periods or abbreviations would make older databases think it was a new entry.
- As you could guess, exclamation points outnumbered periods in her story.
- There are two periods at the end of the last sentence in the first testimonial.
- The dependent clause following the first period appears to be a sentence fragment.
- We use American punctuation standards - put your commas and periods inside your quotation marks.
- Small pauses were commas, larger ones were semicolons and colon; and periods of course were the longest pause of all.
- He often ended interrogatives with periods.
- These marks are very small indeed, about the size of a period at the end of a sentence.
- A name is nothing but two proper nouns with a letter and a period stuck between them.
Synonyms
full stop, full point, point, stop
1. 4.1informal Added to the end of a statement to indicate that no further discussion is possible or desirable.
  〈非正式〉到此为止，就这样（常用于陈述末尾，表示无法或无需再讨论）
  he is the sole owner of the trademark, period
  他是那商标的唯一所有人，就是这样。
  Example sentencesExamples
  He could simply have said he favours public ownership, full stop, period.
  "You hate cats period, " Tiffany reminded her fondly.
  Synonyms
  and that's that, and that is the end of the matter, full stop, finis
5Chemistry
A set of elements occupying a horizontal row in the periodic table.
〔化〕周期元素
Example sentencesExamples
- As we move down the periods, the elements have a greater atomic weight.
- The horizontal rows or periods also have predictable trends in characteristics because as you move left to right in a row only one electron is added changing the atomic number by one.
6Rhetoric
A complex sentence, especially one consisting of several clauses, constructed as part of a formal speech or oration.
〔修辞〕完整句
Example sentencesExamples
- There is frequently poor closure of periods and an inept employment of rhythm in the closure of stanzas and of poems.
1. 6.1Music A complete idea, typically consisting of two or four phrases.
  〔乐〕乐段，乐节
  Example sentencesExamples
  His's an oceanic performance that gives emphasis to the work's undulating hemiolas as they reach across bar lines and destabilize phrase periods.

adjective ˈpɪərɪədˈpɪriəd

attributive Belonging to or characteristic of a past historical time, especially in style or design.
（尤指风格或设计）属于过去某一特定历史时期的；具有过去某一特定历史时期特点的
an attractive and beautifully modernized period house
a splendid selection of period furniture
古老家具精选。
Example sentencesExamples
- He said that period houses of this type and location were among some of the most popular in the city.
- Each of the five apartments is spacious and well-equipped and decorated in period style.
- First performed in 1948, it is interesting today only as a period piece.
- The walls are painted in a soft cream colour and there are period style fireplaces at either end.
- There are eight suites - all decorated by Patricia with French period furniture.
- The hotel's 64 rooms are in comfortable period style, with heavy doors and lots of antiques and arches.
- The room is furnished with expensive period furniture and even an antique gramophone.
- One of the highlights of the weekend will be period re-enactments of historical trials in the old Law Courts in City Hall.
- This stylishly renovated period lodge has been designed to take full advantage of the mature front garden.
- However, although much work was needed, care was taken to preserve the period style of the mansion.
- The owners of one of the most important period houses in Cork are to cut their losses after a bitter planning saga.
- The anniversary of a momentous battle fought only a few miles from York has been marked in period style.
- Some town councillors donned period costume to add to the authenticity of the celebrations.
- They are furnished in period style and presented to the public as representative of a national or regional cultural tradition.
- At the first event some people were unsure about dressing up in period costume.
- This house is a great blend of period qualities and contemporary design.
- This old period house and shop front set beside the bridge and River Moy has a mystique all of its own.
- We are in the early 1970s, with plenty of gleaming period automobiles rolling past on cue.
- A home that has both period style and modern comforts - is it perfection?
- The houses would need to be empty and if they have period furniture and furnishings that would be an extra advantage.
Synonyms
in period style, period, nostalgic, evocative, of yesteryear, olde worlde

Phrases

put a period to

dated Put an end to.
in dry climates, the onset of summer drought may put a period to plant activity
在干燥的气候条件下，夏季干旱的开始就可能使植物丧失活力。
Example sentencesExamples
- ‘They say they want to put a period to my presidency.’
- Plot had not originally intended to include such material in the book since he believed that the chapter on arts had ‘finish'd the Natural History of Oxford-shire’ and prompted him ‘accordingly [to] here put a period to my Essay!’
- After all, he alone correctly predicted her response, warning him that she could not outlive the ‘perpetrated outrage,’ and that ‘wasting grief [would] put a period to her days ’.
- Why are you determined to put a period to your own existence if his is the pistol that's primed?
- Then there's a lull; people stare into their empty glasses, then pat the table with open palms and put a period to our merry night.
Synonyms
bring to an end, bring to a close, finish, close, wind up, terminate, dissolve

Origin

Late Middle English (denoting the time during which something, especially a disease, runs its course): from Old French periode, via Latin from Greek periodos 'orbit, recurrence, course', from peri- 'around' + hodos 'way, course'. The sense 'portion of time' dates from the early 17th century.

When first used, period referred to the time during which something such as a disease, ran its course. It goes back to Greek periodos ‘orbit, recurrence, course’, from peri- ‘around’ and hodos ‘way’. The sense ‘portion of time’ dates from the early 17th century, as does use of the word to mean ‘full stop’, now part of US English. Peri is also found in peripatetic (Late Middle English) now meaning ‘wandering, travelling’ but from Greek peripatetikos ‘walking up and down’ and originally applied to followers of the ideas of Aristotle (384–322 bc), who is said to have walked about while teaching; and periphery (late 16th century) originally the boundary of something. Hodos, the second part of period is also found in episode (late 17th century), literally ‘coming in beside’ from epi ‘addition’ and eisodos ‘entry’ (formed from eis ‘into’ and hodos); and exodus, ‘departure’ formed in the same way using ex- ‘out of’. See also method

Definition of period in US English:

period

nounˈpɪriədˈpirēəd

1A length or portion of time.
（一段）时间，时期，阶段
he had long periods of depression
他几次陷入长时间的消沉。
the period 1977–85
1977-1985年这一时期。
the training period is between 16 and 18 months
训练期是16到18个月。
the ale will be available for a limited period
麦芽酒只供应有限的一段时间。
Example sentencesExamples
- One of the most enjoyable events in Bolivia is Carnival, the period preceding Lent.
- It is fascinating to relate aerial photographs to maps of all periods, especially on the coast where continuous erosion and deposits often show extravagant change over relatively short periods of time.
- On release from prison he will have to serve an extended two-year period on licence.
- Hauling and applying manure may require large blocks of time for relatively short periods throughout the year.
- The 1980s were a hectic period in his personal life.
- The file dates span the period between September 1996 and April 1997.
- Generally, consumers have accepted the relatively short periods of 14 to 21 days for half or full gallons of milk.
- Unlike here, there has been a significant increase in supply following the long period of inactivity.
- Hopefully, the pertinent questions will be asked after the initial period of mourning.
- Both males and females undergo periods of inactivity from November until March.
- They extend the grace period for the repayment of the loan till March 2006.
- A military judge can extend the period of detention incommunicado up to 90 days.
- The survey covered the one-year period ending November, 2003.
- The fluvial sediments, however, represent rapid deposition in relatively short periods (days or months).
- Benefits are usually offered after a six-month probationary period and backdated to the start of employment.
- After all, a new president enjoys a honeymoon period of three months at most.
- These results show that spectacular gains may be made in relatively short periods from what may have seemed the least likely candidates.
- She hadn't left Hong Kong during the two-week incubation period, it said.
- They are born in relatively short periods after long periods of social disintegration.
- The prediction is based on the crimes committed so far in the period under review.
Synonyms
time, spell, interval, stretch, term, span, phase, session, bout, run, space, duration, chapter, stage
1. 1.1 A portion of time in the life of a nation, civilization, etc. characterized by the same prevalent features or conditions.
  阶段；时代
  the early medieval period
  中世纪的早期。
  Example sentencesExamples
  Life at the bottom of society was always difficult in the late medieval and early modern periods: but around 1600 conditions for many of the poor were terrible.
  Nevertheless, the eighteenth century was a period of rapid urban growth.
  Magical beliefs and practices existed at all social levels in the medieval and early modern periods, and were enmeshed in medical and scientific thought and techniques.
  His work has focused on the medieval and early modern periods.
  The life that one sacrificed to God or king in the medieval and early modern periods became, with the advent of modernity, a life offered in the name of one's country.
  The art forms that emerged in the early period of civilisation are primitive and catered to a people who had no alternative.
  The late 1950s and early 1960s were a period of expansion and creativity.
  The nineteenth century was a period of unparalleled imperial expansion.
  This strong connection between politics and music is a feature of the period.
  The early 1990s also was a period of persistently sluggish growth - in credit, employment and GDP.
  If we confine ourselves to Europe in the late medieval and early modern periods, we find that at least initial studies have been completed on England, France, Amsterdam, and parts of Germany.
  You said we entered a dark period in American history.
  The Book of Kells is one of the great masterpieces that has come down to us from a period often referred to as the Dark Ages.
  Economists and historians regard a reduction in real wages as one of the distinguishing features of the modern period.
  Also featured will be works from the Byzantine, Medieval, and Renaissance periods, as well as late 18th and early 19th century art.
  To be sure, the public prayer forms of the West needed culling and refining by the late medieval and early Renaissance periods.
  In these, information about the history of the regions and archaeological discoveries bring the Viking and early medieval periods to life.
  Yet the 1990s was a very robust period of growth.
  We have entered a critical period in financial history.
  Of these, 98 per cent cover the 19th and 20th centuries, while only 16 per cent cover medieval or earlier periods.
  Synonyms
  era, age, epoch, time, days, years, aeon
2. 1.2 A major division of geological time that is a subdivision of an era and is itself subdivided into epochs, corresponding to a system in chronostratigraphy.
  （地质年代划分的）纪
  Example sentencesExamples
  The event, known as the Great Dying, occurred about 250 million years ago at the boundary between the Permian and Triassic periods.
  Because the Miocene is closer to the present day than most other periods of geologic time, it is easier to see the effects of events, and to interpret patterns.
  Because of this, clay becomes progressively less common in older geological periods and is almost never found in Precambrian formations.
  Evolutionists say these formations represent three different geological periods ranging from 35 to 245 million years.
  During the Cretaceous and the Tertiary periods large parts of the present subcontinent of India were flooded by multiple lava flows.
  The following table shows the three eras and eleven geological periods that comprise the Phanerozoic.
  Geological periods are defined with reference to a Global Boundary Stratotype Section and Point.
  The Mesozoic era lasted from about 251 to 66 million years ago and includes the Triassic, Jurassic, and Cretaceous periods.
  We have additional information on the geological time periods along the top of the image.
  Despite our lack of knowledge, or perhaps because of it, researchers have divided the Precambrian into three time periods called eons.
  The extinction occurred at the boundary between the Permian and Triassic periods at a time when all land was concentrated in a supercontinent called Pangea.
  The Great Dying occurred between the Permian and Triassic periods, when all of today's continents were concentrated in one great land mass called Pangea.
  This was accompanied by the multistage emplacement of large intrusive bodies in the Cambrian, Ordovician, and Silurian periods.
  In contrast, dinosaur fossils have been traced in Triassic, Jurassic and Cretaceous periods.
  Historically, the Cenozoic has been divided up into the Quaternary and Tertiary sub-eras, as well as the Neogene and Paleogene periods.
  Most are restricted to one or two geologic periods, and a few contain only one genus.
  This book shows the dynamic effects of the many periods of Pleistocene glacial advance and melting on the geology and topography of the northwestern United States.
  Later geological periods show similar patterns of sudden appearance, stasis and persistent chasms of difference between major groups.
  The right-hand column lists the six major epochs into which the periods are divided.
  Extinctions have also occurred in all other periods of geological time.
3. 1.3 One of the set divisions of the day in a school allocated to a lesson or other activity.
  学时，课时
  Example sentencesExamples
  The two of them reached the door to their first period study hall room.
  In my day, that meant the four boys who drank it in an alley near school during free periods (I joined them once and will spare you the details).
  Most of my teachers were unaware of my hours of research in the school library; the reason for this was that I was supposed to be doing something else in my free periods, so I kept quiet about what I was doing.
  Nothing could bring him down… until he reached his third period Algebra class.
  Despite the fact that this lesson took several class periods to complete, I feel it was definitely worth it.
  Uh, you really need to take this up next period in your Comparative Religion class.
  To accommodate the rich level of activity hoped for in his mathematical laboratory, he proposed that two consecutive class periods be allocated to it.
  Even the teacher was very interested in the argument, so she gave the class a free period.
  When I was looking for my third period class which is Health, the halls were really crowded.
  Walking down the hallway towards first period trigonometry Jordan smiled as she passed people.
  Teachers should also be in classrooms for all the periods allocated to them and those who served as councillors should be filled in for, he said.
  The total lesson takes several class periods and I recite the poems to motivate my young artists many times throughout the lesson.
  Youngsters coming out of school during free periods were also blamed for trouble in the town.
  I would look at it later and make sense of it but, as for now, I had to get to my next lesson because the free period would probably be nearing an end.
  My parents were a bit worried when they saw all the free periods in my timetable.
  I took a seat in the middle near the window in my fourth period class which was art.
  By the time I got to class, the first period bell was ringing.
  I never really got why lessons were called periods.
  James had a free for periods five and six, so he was in the IT room, out of the cold.
  Dumping her test into the inbox she left the classroom for fourth period Health.
  Synonyms
  lesson, class, session
4. 1.4 Each of the intervals into which the playing time of a sporting event is divided.
  （体育比赛的）局
  Example sentencesExamples
  There were no goals in the first period of extra time but within a minute of the restart a through-ball fell to Bowers, who made no mistake.
  However, with almost the last kick of the game, he scored the winning point in the fourth period of extra time.
  Between periods in the locker rooms, IVs drip fluids into dehydrated athletes, who eat bananas and drink even more liquids to fight off cramping.
  In the second period of extra time United pushed hard looking again for another equaliser.
  Venezuela was reduced to ten players for the second period of extra time and the pressure shifted to Uruguay.
  In the first period of extra time both teams played at a frenetic pace with tenacious defending keeping Keighley's hopes alive.
  They totally dominated the first period, scoring five and conceding one.
  A tense period of extra-time failed to produce a winning goal for either team.
  The second period of extra time saw the home side get a goal back.
  There have been 17 periods of extra time in European Championships and World Cups since the Golden Goal system began at Euro 96.
  Teams play full periods with no TV timeouts - the ultimate test of conditioning.
  He also missed a 30m penalty in the first period of extra time.
  There is an extra period called injury time, usually in the vicinity of three minutes.
  The match ended scoreless in normal time, but the team conceded a goal in the first period of extra time.
  Kinsale scored the decisive second goal three minutes into the first period of extra-time.
  Why is a penalty in the first period of a game in December not a penalty in the third period of a game in March?
  If games are tied at full-time an extra period will be played with the first team to score winning the game.
  They turned into gaping holes in the final period when three Belfast goals in as many minutes ended the contest.
  His save percentage and GAA in the third period is better than in the first two periods.
  But, once he scored in the sixth minute of the injury time, the script for the extra time periods could have been written.
2Physics
The interval of time between successive occurrences of the same state in an oscillatory or cyclic phenomenon, such as a mechanical vibration, an alternating current, a variable star, or an electromagnetic wave.
〔物理〕（振动或循环的）周期
Example sentencesExamples
- To produce a larger effect, the motion must accumulate, and for wave-impulses to accumulate, they must arrive in periods identical with the periods of vibration of the atoms on which they impinge.
1. 2.1Astronomy The time taken by a celestial object to rotate around its axis, or to make one circuit of its orbit.
  〔天文〕自转（或公转）周期
  Example sentencesExamples
  The atmosphere rotates with periods ranging from over 18 hours near the equator to faster than 13 hours near the poles.
  The first problem Galileo attacked at Florence was to determine orbits and periods for Jupiter's four satellites.
  Certainly the book would be more compelling if it contained a success story on a par with accounting for the periods of the planetary orbits or the perihelion shift of Mercury.
  Typical distances from the Sun are 10,000 astronomical units, and typical orbital periods are on the order of 1 million years.
  In contrast, Jupiter-family comets tend to have predictable, well-determined orbits with short periods and low inclinations.
2. 2.2Mathematics The interval between successive equal values of a periodic function.
  〔数〕（周期函数的）周期
  Example sentencesExamples
  What is the period of the continued fractions of the following numbers?
  In 1834 Jacobi proved that if a single-valued function of one variable is doubly periodic then the ratio of the periods is imaginary.
3A flow of blood and other material from the lining of the uterus, lasting for several days and occurring in sexually mature women who are not pregnant at intervals of about one lunar month until the onset of menopause.
（妇女的）经期
Example sentencesExamples
- Three standard gynecological texts state that the commonly observed interval between menstrual periods is 26 to 30 days, 24 to 32 days, and 24 to 35 days.
- If a woman does not have periods (due to menopause or removal of uterus), then it may be done on a fixed day of the month.
- It affects women much more often than men, because women lose some blood in each menstrual period between puberty and the menopause.
- During puberty or nearing menopause, many women have irregular periods so no treatment is necessary.
- Women who receive chemotherapy may have a change in their periods or menstrual cycles.
- Some older women think the absence of periods is related to menopause and not pregnancy.
- It mostly affects women between the ages of 50 and 70, who have been through the menopause (when your periods stop).
- Sometimes the cause is clear, for example in women who are pregnant or have heavy periods.
- You then need to use progesterone pessaries until your periods start again.
- Amenorrhea just means an absence of menstrual cycles or periods for at least about three to six months, and the particular type of amenorrhea that we were studying is called hypothalamic.
- Because sex during menstruation may increase the chances of transmitting or contracting HIV, it may be safer for women to wait until their periods are over to have sex.
- During early pregnancy, some women develop acne, especially those who were prone to breakouts during menstrual periods before becoming pregnant.
- A headache diary may be necessary to confirm the relationship between migraine and menstruation, especially if periods are irregular.
- Amenorrhoea is the absence of periods (menstruation).
- Most women have some crampy pain with their periods, especially as teenagers.
- Many women don't suspect they're pregnant until their period doesn't arrive.
- About 60% of women who say they have heavy periods are found to have normal periods when their blood loss is measured.
- Women may also experience painful periods and pain during sexual intercourse.
- It is common to have heavy blood flow at the beginning of a period and lighter blood flow at the end.
- Examples include when a partner leaves, pregnancies among very young women, those with irregular periods or at the menopause, or when testing has shown a baby with abnormalities.
Synonyms
menstruation, menstrual flow
4North American A punctuation mark (.) used at the end of a sentence or an abbreviation.
British term full stop
Example sentencesExamples
- He put a period on the end of the last sentence, and placed the pen down with a loud sound and looked up at her.
- Small pauses were commas, larger ones were semicolons and colon; and periods of course were the longest pause of all.
- The dependent clause following the first period appears to be a sentence fragment.
- A name is nothing but two proper nouns with a letter and a period stuck between them.
- The first sentence should have been ended with a period and not a question mark.
- There are two periods at the end of the last sentence in the first testimonial.
- These marks are very small indeed, about the size of a period at the end of a sentence.
- As you could guess, exclamation points outnumbered periods in her story.
- Simple input issues such as periods or abbreviations would make older databases think it was a new entry.
- He often ended interrogatives with periods.
- We use American punctuation standards - put your commas and periods inside your quotation marks.
- The dominant American style is to include commas and periods within quotation marks even when that punctuation doesn't belong to the quotation.
- As he talked he jabbed the lit end of his cigar into the air as though he were punctuating his sentences by burning periods in the air.
Synonyms
full stop, full point, point, stop
1. 4.1informal Added to the end of a statement to indicate that no further discussion is possible or desirable.
  〈非正式〉到此为止，就这样（常用于陈述末尾，表示无法或无需再讨论）
  he is the sole owner of the trademark, period
  他是那商标的唯一所有人，就是这样。
  Example sentencesExamples
  "You hate cats period, " Tiffany reminded her fondly.
  He could simply have said he favours public ownership, full stop, period.
  Synonyms
  and that's that, and that is the end of the matter, full stop, finis
5Chemistry
A set of elements occupying an entire horizontal row in the periodic table.
〔化〕周期元素
Example sentencesExamples
- As we move down the periods, the elements have a greater atomic weight.
- The horizontal rows or periods also have predictable trends in characteristics because as you move left to right in a row only one electron is added changing the atomic number by one.
6Rhetoric
A complex sentence, especially one consisting of several clauses, constructed as part of a formal speech or oration.
〔修辞〕完整句
Example sentencesExamples
- There is frequently poor closure of periods and an inept employment of rhythm in the closure of stanzas and of poems.
1. 6.1Music A complete idea, typically consisting of two or four phrases.
  〔乐〕乐段，乐节
  Example sentencesExamples
  His's an oceanic performance that gives emphasis to the work's undulating hemiolas as they reach across bar lines and destabilize phrase periods.

adjectiveˈpɪriədˈpirēəd

attributive Belonging to or characteristic of a past historical time, especially in style or design.
（尤指风格或设计）属于过去某一特定历史时期的；具有过去某一特定历史时期特点的
a splendid selection of period furniture
古老家具精选。
Example sentencesExamples
- The houses would need to be empty and if they have period furniture and furnishings that would be an extra advantage.
- The owners of one of the most important period houses in Cork are to cut their losses after a bitter planning saga.
- At the first event some people were unsure about dressing up in period costume.
- We are in the early 1970s, with plenty of gleaming period automobiles rolling past on cue.
- They are furnished in period style and presented to the public as representative of a national or regional cultural tradition.
- A home that has both period style and modern comforts - is it perfection?
- He said that period houses of this type and location were among some of the most popular in the city.
- This old period house and shop front set beside the bridge and River Moy has a mystique all of its own.
- The hotel's 64 rooms are in comfortable period style, with heavy doors and lots of antiques and arches.
- This stylishly renovated period lodge has been designed to take full advantage of the mature front garden.
- The walls are painted in a soft cream colour and there are period style fireplaces at either end.
- This house is a great blend of period qualities and contemporary design.
- The room is furnished with expensive period furniture and even an antique gramophone.
- However, although much work was needed, care was taken to preserve the period style of the mansion.
- First performed in 1948, it is interesting today only as a period piece.
- The anniversary of a momentous battle fought only a few miles from York has been marked in period style.
- Some town councillors donned period costume to add to the authenticity of the celebrations.
- There are eight suites - all decorated by Patricia with French period furniture.
- One of the highlights of the weekend will be period re-enactments of historical trials in the old Law Courts in City Hall.
- Each of the five apartments is spacious and well-equipped and decorated in period style.
Synonyms
in period style, period, nostalgic, evocative, of yesteryear, olde worlde

Origin

Late Middle English (denoting the time during which something, especially a disease, runs its course): from Old French periode, via Latin from Greek periodos ‘orbit, recurrence, course’, from peri- ‘around’ + hodos ‘way, course’. The sense ‘portion of time’ dates from the early 17th century.

词汇	period
释义	Definition of period in English: period noun ˈpɪərɪədˈpɪriəd 1A length or portion of time. （一段）时间，时期，阶段 he had long periods of depression 他几次陷入长时间的消沉。 the period 1977–85 1977-1985年这一时期。 the training period is between 16 and 18 months 训练期是16到18个月。 Example sentencesExamples The fluvial sediments, however, represent rapid deposition in relatively short periods (days or months). They are born in relatively short periods after long periods of social disintegration. Generally, consumers have accepted the relatively short periods of 14 to 21 days for half or full gallons of milk. She hadn't left Hong Kong during the two-week incubation period, it said. One of the most enjoyable events in Bolivia is Carnival, the period preceding Lent. The prediction is based on the crimes committed so far in the period under review. They extend the grace period for the repayment of the loan till March 2006. After all, a new president enjoys a honeymoon period of three months at most. It is fascinating to relate aerial photographs to maps of all periods, especially on the coast where continuous erosion and deposits often show extravagant change over relatively short periods of time. Both males and females undergo periods of inactivity from November until March. Unlike here, there has been a significant increase in supply following the long period of inactivity. The file dates span the period between September 1996 and April 1997. Hopefully, the pertinent questions will be asked after the initial period of mourning. Benefits are usually offered after a six-month probationary period and backdated to the start of employment. The 1980s were a hectic period in his personal life. These results show that spectacular gains may be made in relatively short periods from what may have seemed the least likely candidates. A military judge can extend the period of detention incommunicado up to 90 days. On release from prison he will have to serve an extended two-year period on licence. The survey covered the one-year period ending November, 2003. Hauling and applying manure may require large blocks of time for relatively short periods throughout the year. Synonyms time, spell, interval, stretch, term, span, phase, session, bout, run, space, duration, chapter, stage while British informal patch 1.1 A portion of time in the life of a nation, civilization, etc. characterized by the same prevalent features or conditions. 阶段；时代 the early medieval period 中世纪的早期。 Example sentencesExamples Also featured will be works from the Byzantine, Medieval, and Renaissance periods, as well as late 18th and early 19th century art. The art forms that emerged in the early period of civilisation are primitive and catered to a people who had no alternative. If we confine ourselves to Europe in the late medieval and early modern periods, we find that at least initial studies have been completed on England, France, Amsterdam, and parts of Germany. Life at the bottom of society was always difficult in the late medieval and early modern periods: but around 1600 conditions for many of the poor were terrible. The early 1990s also was a period of persistently sluggish growth - in credit, employment and GDP. The late 1950s and early 1960s were a period of expansion and creativity. Of these, 98 per cent cover the 19th and 20th centuries, while only 16 per cent cover medieval or earlier periods. This strong connection between politics and music is a feature of the period. In these, information about the history of the regions and archaeological discoveries bring the Viking and early medieval periods to life. The nineteenth century was a period of unparalleled imperial expansion. Magical beliefs and practices existed at all social levels in the medieval and early modern periods, and were enmeshed in medical and scientific thought and techniques. You said we entered a dark period in American history. To be sure, the public prayer forms of the West needed culling and refining by the late medieval and early Renaissance periods. Nevertheless, the eighteenth century was a period of rapid urban growth. We have entered a critical period in financial history. The life that one sacrificed to God or king in the medieval and early modern periods became, with the advent of modernity, a life offered in the name of one's country. The Book of Kells is one of the great masterpieces that has come down to us from a period often referred to as the Dark Ages. Yet the 1990s was a very robust period of growth. His work has focused on the medieval and early modern periods. Economists and historians regard a reduction in real wages as one of the distinguishing features of the modern period. Synonyms era, age, epoch, time, days, years, aeon generation, date 1.2 A major division of geological time that is a subdivision of an era and is itself subdivided into epochs. （地质年代划分的）纪 the Cretaceous period Example sentencesExamples The following table shows the three eras and eleven geological periods that comprise the Phanerozoic. The event, known as the Great Dying, occurred about 250 million years ago at the boundary between the Permian and Triassic periods. Despite our lack of knowledge, or perhaps because of it, researchers have divided the Precambrian into three time periods called eons. Later geological periods show similar patterns of sudden appearance, stasis and persistent chasms of difference between major groups. This was accompanied by the multistage emplacement of large intrusive bodies in the Cambrian, Ordovician, and Silurian periods. Because of this, clay becomes progressively less common in older geological periods and is almost never found in Precambrian formations. In contrast, dinosaur fossils have been traced in Triassic, Jurassic and Cretaceous periods. Historically, the Cenozoic has been divided up into the Quaternary and Tertiary sub-eras, as well as the Neogene and Paleogene periods. This book shows the dynamic effects of the many periods of Pleistocene glacial advance and melting on the geology and topography of the northwestern United States. Because the Miocene is closer to the present day than most other periods of geologic time, it is easier to see the effects of events, and to interpret patterns. Evolutionists say these formations represent three different geological periods ranging from 35 to 245 million years. The extinction occurred at the boundary between the Permian and Triassic periods at a time when all land was concentrated in a supercontinent called Pangea. Geological periods are defined with reference to a Global Boundary Stratotype Section and Point. The Mesozoic era lasted from about 251 to 66 million years ago and includes the Triassic, Jurassic, and Cretaceous periods. During the Cretaceous and the Tertiary periods large parts of the present subcontinent of India were flooded by multiple lava flows. The right-hand column lists the six major epochs into which the periods are divided. Extinctions have also occurred in all other periods of geological time. The Great Dying occurred between the Permian and Triassic periods, when all of today's continents were concentrated in one great land mass called Pangea. Most are restricted to one or two geologic periods, and a few contain only one genus. We have additional information on the geological time periods along the top of the image. 1.3 Each of the set divisions of the day in a school allocated to a lesson or other activity. 学时，课时 two periods of PE are allocated on the timetable he interviewed the teachers when they had a free period Example sentencesExamples Walking down the hallway towards first period trigonometry Jordan smiled as she passed people. Teachers should also be in classrooms for all the periods allocated to them and those who served as councillors should be filled in for, he said. I would look at it later and make sense of it but, as for now, I had to get to my next lesson because the free period would probably be nearing an end. Despite the fact that this lesson took several class periods to complete, I feel it was definitely worth it. Dumping her test into the inbox she left the classroom for fourth period Health. Even the teacher was very interested in the argument, so she gave the class a free period. By the time I got to class, the first period bell was ringing. Youngsters coming out of school during free periods were also blamed for trouble in the town. When I was looking for my third period class which is Health, the halls were really crowded. The two of them reached the door to their first period study hall room. I never really got why lessons were called periods. My parents were a bit worried when they saw all the free periods in my timetable. Uh, you really need to take this up next period in your Comparative Religion class. James had a free for periods five and six, so he was in the IT room, out of the cold. Nothing could bring him down… until he reached his third period Algebra class. In my day, that meant the four boys who drank it in an alley near school during free periods (I joined them once and will spare you the details). Most of my teachers were unaware of my hours of research in the school library; the reason for this was that I was supposed to be doing something else in my free periods, so I kept quiet about what I was doing. I took a seat in the middle near the window in my fourth period class which was art. To accommodate the rich level of activity hoped for in his mathematical laboratory, he proposed that two consecutive class periods be allocated to it. The total lesson takes several class periods and I recite the poems to motivate my young artists many times throughout the lesson. Synonyms lesson, class, session 1.4 Each of the divisions of the playing time of a sporting event. （体育比赛的）局 the Lightnings ran at the Leafs hard in a very rough first period Example sentencesExamples Between periods in the locker rooms, IVs drip fluids into dehydrated athletes, who eat bananas and drink even more liquids to fight off cramping. He also missed a 30m penalty in the first period of extra time. Kinsale scored the decisive second goal three minutes into the first period of extra-time. But, once he scored in the sixth minute of the injury time, the script for the extra time periods could have been written. If games are tied at full-time an extra period will be played with the first team to score winning the game. There is an extra period called injury time, usually in the vicinity of three minutes. A tense period of extra-time failed to produce a winning goal for either team. Why is a penalty in the first period of a game in December not a penalty in the third period of a game in March? However, with almost the last kick of the game, he scored the winning point in the fourth period of extra time. The second period of extra time saw the home side get a goal back. His save percentage and GAA in the third period is better than in the first two periods. Venezuela was reduced to ten players for the second period of extra time and the pressure shifted to Uruguay. They turned into gaping holes in the final period when three Belfast goals in as many minutes ended the contest. Teams play full periods with no TV timeouts - the ultimate test of conditioning. In the first period of extra time both teams played at a frenetic pace with tenacious defending keeping Keighley's hopes alive. There were no goals in the first period of extra time but within a minute of the restart a through-ball fell to Bowers, who made no mistake. In the second period of extra time United pushed hard looking again for another equaliser. They totally dominated the first period, scoring five and conceding one. The match ended scoreless in normal time, but the team conceded a goal in the first period of extra time. There have been 17 periods of extra time in European Championships and World Cups since the Golden Goal system began at Euro 96. 2Physics The interval of time between successive occurrences of the same state in an oscillatory or cyclic phenomenon, such as a mechanical vibration, an alternating current, a variable star, or an electromagnetic wave. 〔物理〕（振动或循环的）周期 Example sentencesExamples To produce a larger effect, the motion must accumulate, and for wave-impulses to accumulate, they must arrive in periods identical with the periods of vibration of the atoms on which they impinge. 2.1Astronomy The time taken by a celestial object to rotate about its axis, or to make one circuit of its orbit. 〔天文〕自转（或公转）周期 Example sentencesExamples Certainly the book would be more compelling if it contained a success story on a par with accounting for the periods of the planetary orbits or the perihelion shift of Mercury. In contrast, Jupiter-family comets tend to have predictable, well-determined orbits with short periods and low inclinations. Typical distances from the Sun are 10,000 astronomical units, and typical orbital periods are on the order of 1 million years. The atmosphere rotates with periods ranging from over 18 hours near the equator to faster than 13 hours near the poles. The first problem Galileo attacked at Florence was to determine orbits and periods for Jupiter's four satellites. 2.2Mathematics The interval between successive equal values of a periodic function. 〔数〕（周期函数的）周期 Example sentencesExamples In 1834 Jacobi proved that if a single-valued function of one variable is doubly periodic then the ratio of the periods is imaginary. What is the period of the continued fractions of the following numbers? 3A flow of blood and other material from the lining of the uterus, lasting for a few days and occurring in sexually mature women who are not pregnant at intervals of about one lunar month until the menopause. （妇女的）经期 she's got her period as modifier period pains Example sentencesExamples Examples include when a partner leaves, pregnancies among very young women, those with irregular periods or at the menopause, or when testing has shown a baby with abnormalities. Many women don't suspect they're pregnant until their period doesn't arrive. During early pregnancy, some women develop acne, especially those who were prone to breakouts during menstrual periods before becoming pregnant. It mostly affects women between the ages of 50 and 70, who have been through the menopause (when your periods stop). Because sex during menstruation may increase the chances of transmitting or contracting HIV, it may be safer for women to wait until their periods are over to have sex. If a woman does not have periods (due to menopause or removal of uterus), then it may be done on a fixed day of the month. During puberty or nearing menopause, many women have irregular periods so no treatment is necessary. About 60% of women who say they have heavy periods are found to have normal periods when their blood loss is measured. It affects women much more often than men, because women lose some blood in each menstrual period between puberty and the menopause. Women may also experience painful periods and pain during sexual intercourse. Most women have some crampy pain with their periods, especially as teenagers. Some older women think the absence of periods is related to menopause and not pregnancy. Sometimes the cause is clear, for example in women who are pregnant or have heavy periods. A headache diary may be necessary to confirm the relationship between migraine and menstruation, especially if periods are irregular. Amenorrhea just means an absence of menstrual cycles or periods for at least about three to six months, and the particular type of amenorrhea that we were studying is called hypothalamic. You then need to use progesterone pessaries until your periods start again. Women who receive chemotherapy may have a change in their periods or menstrual cycles. Three standard gynecological texts state that the commonly observed interval between menstrual periods is 26 to 30 days, 24 to 32 days, and 24 to 35 days. Amenorrhoea is the absence of periods (menstruation). It is common to have heavy blood flow at the beginning of a period and lighter blood flow at the end. Synonyms menstruation, menstrual flow informal the curse, monthlies, time of the month technical menses archaic time rare flowers 4North American A punctuation mark (.) used at the end of a sentence or an abbreviation; a full stop. Example sentencesExamples The dominant American style is to include commas and periods within quotation marks even when that punctuation doesn't belong to the quotation. As he talked he jabbed the lit end of his cigar into the air as though he were punctuating his sentences by burning periods in the air. He put a period on the end of the last sentence, and placed the pen down with a loud sound and looked up at her. The first sentence should have been ended with a period and not a question mark. Simple input issues such as periods or abbreviations would make older databases think it was a new entry. As you could guess, exclamation points outnumbered periods in her story. There are two periods at the end of the last sentence in the first testimonial. The dependent clause following the first period appears to be a sentence fragment. We use American punctuation standards - put your commas and periods inside your quotation marks. Small pauses were commas, larger ones were semicolons and colon; and periods of course were the longest pause of all. He often ended interrogatives with periods. These marks are very small indeed, about the size of a period at the end of a sentence. A name is nothing but two proper nouns with a letter and a period stuck between them. Synonyms full stop, full point, point, stop 4.1informal Added to the end of a statement to indicate that no further discussion is possible or desirable. 〈非正式〉到此为止，就这样（常用于陈述末尾，表示无法或无需再讨论） he is the sole owner of the trademark, period 他是那商标的唯一所有人，就是这样。 Example sentencesExamples He could simply have said he favours public ownership, full stop, period. "You hate cats period, " Tiffany reminded her fondly. Synonyms and that's that, and that is the end of the matter, full stop, finis 5Chemistry A set of elements occupying a horizontal row in the periodic table. 〔化〕周期元素 Example sentencesExamples As we move down the periods, the elements have a greater atomic weight. The horizontal rows or periods also have predictable trends in characteristics because as you move left to right in a row only one electron is added changing the atomic number by one. 6Rhetoric A complex sentence, especially one consisting of several clauses, constructed as part of a formal speech or oration. 〔修辞〕完整句 Example sentencesExamples There is frequently poor closure of periods and an inept employment of rhythm in the closure of stanzas and of poems. 6.1Music A complete idea, typically consisting of two or four phrases. 〔乐〕乐段，乐节 Example sentencesExamples His's an oceanic performance that gives emphasis to the work's undulating hemiolas as they reach across bar lines and destabilize phrase periods. adjective ˈpɪərɪədˈpɪriəd attributive Belonging to or characteristic of a past historical time, especially in style or design. （尤指风格或设计）属于过去某一特定历史时期的；具有过去某一特定历史时期特点的 an attractive and beautifully modernized period house a splendid selection of period furniture 古老家具精选。 Example sentencesExamples He said that period houses of this type and location were among some of the most popular in the city. Each of the five apartments is spacious and well-equipped and decorated in period style. First performed in 1948, it is interesting today only as a period piece. The walls are painted in a soft cream colour and there are period style fireplaces at either end. There are eight suites - all decorated by Patricia with French period furniture. The hotel's 64 rooms are in comfortable period style, with heavy doors and lots of antiques and arches. The room is furnished with expensive period furniture and even an antique gramophone. One of the highlights of the weekend will be period re-enactments of historical trials in the old Law Courts in City Hall. This stylishly renovated period lodge has been designed to take full advantage of the mature front garden. However, although much work was needed, care was taken to preserve the period style of the mansion. The owners of one of the most important period houses in Cork are to cut their losses after a bitter planning saga. The anniversary of a momentous battle fought only a few miles from York has been marked in period style. Some town councillors donned period costume to add to the authenticity of the celebrations. They are furnished in period style and presented to the public as representative of a national or regional cultural tradition. At the first event some people were unsure about dressing up in period costume. This house is a great blend of period qualities and contemporary design. This old period house and shop front set beside the bridge and River Moy has a mystique all of its own. We are in the early 1970s, with plenty of gleaming period automobiles rolling past on cue. A home that has both period style and modern comforts - is it perfection? The houses would need to be empty and if they have period furniture and furnishings that would be an extra advantage. Synonyms in period style, period, nostalgic, evocative, of yesteryear, olde worlde Phrases put a period to dated Put an end to. in dry climates, the onset of summer drought may put a period to plant activity 在干燥的气候条件下，夏季干旱的开始就可能使植物丧失活力。 Example sentencesExamples ‘They say they want to put a period to my presidency.’ Plot had not originally intended to include such material in the book since he believed that the chapter on arts had ‘finish'd the Natural History of Oxford-shire’ and prompted him ‘accordingly [to] here put a period to my Essay!’ After all, he alone correctly predicted her response, warning him that she could not outlive the ‘perpetrated outrage,’ and that ‘wasting grief [would] put a period to her days ’. Why are you determined to put a period to your own existence if his is the pistol that's primed? Then there's a lull; people stare into their empty glasses, then pat the table with open palms and put a period to our merry night. Synonyms bring to an end, bring to a close, finish, close, wind up, terminate, dissolve Origin Late Middle English (denoting the time during which something, especially a disease, runs its course): from Old French periode, via Latin from Greek periodos 'orbit, recurrence, course', from peri- 'around' + hodos 'way, course'. The sense 'portion of time' dates from the early 17th century. When first used, period referred to the time during which something such as a disease, ran its course. It goes back to Greek periodos ‘orbit, recurrence, course’, from peri- ‘around’ and hodos ‘way’. The sense ‘portion of time’ dates from the early 17th century, as does use of the word to mean ‘full stop’, now part of US English. Peri is also found in peripatetic (Late Middle English) now meaning ‘wandering, travelling’ but from Greek peripatetikos ‘walking up and down’ and originally applied to followers of the ideas of Aristotle (384–322 bc), who is said to have walked about while teaching; and periphery (late 16th century) originally the boundary of something. Hodos, the second part of period is also found in episode (late 17th century), literally ‘coming in beside’ from epi ‘addition’ and eisodos ‘entry’ (formed from eis ‘into’ and hodos); and exodus, ‘departure’ formed in the same way using ex- ‘out of’. See also method noun.1 phr. Definition of period in US English: period nounˈpɪriədˈpirēəd 1A length or portion of time. （一段）时间，时期，阶段 he had long periods of depression 他几次陷入长时间的消沉。 the period 1977–85 1977-1985年这一时期。 the training period is between 16 and 18 months 训练期是16到18个月。 the ale will be available for a limited period 麦芽酒只供应有限的一段时间。 Example sentencesExamples One of the most enjoyable events in Bolivia is Carnival, the period preceding Lent. It is fascinating to relate aerial photographs to maps of all periods, especially on the coast where continuous erosion and deposits often show extravagant change over relatively short periods of time. On release from prison he will have to serve an extended two-year period on licence. Hauling and applying manure may require large blocks of time for relatively short periods throughout the year. The 1980s were a hectic period in his personal life. The file dates span the period between September 1996 and April 1997. Generally, consumers have accepted the relatively short periods of 14 to 21 days for half or full gallons of milk. Unlike here, there has been a significant increase in supply following the long period of inactivity. Hopefully, the pertinent questions will be asked after the initial period of mourning. Both males and females undergo periods of inactivity from November until March. They extend the grace period for the repayment of the loan till March 2006. A military judge can extend the period of detention incommunicado up to 90 days. The survey covered the one-year period ending November, 2003. The fluvial sediments, however, represent rapid deposition in relatively short periods (days or months). Benefits are usually offered after a six-month probationary period and backdated to the start of employment. After all, a new president enjoys a honeymoon period of three months at most. These results show that spectacular gains may be made in relatively short periods from what may have seemed the least likely candidates. She hadn't left Hong Kong during the two-week incubation period, it said. They are born in relatively short periods after long periods of social disintegration. The prediction is based on the crimes committed so far in the period under review. Synonyms time, spell, interval, stretch, term, span, phase, session, bout, run, space, duration, chapter, stage 1.1 A portion of time in the life of a nation, civilization, etc. characterized by the same prevalent features or conditions. 阶段；时代 the early medieval period 中世纪的早期。 Example sentencesExamples Life at the bottom of society was always difficult in the late medieval and early modern periods: but around 1600 conditions for many of the poor were terrible. Nevertheless, the eighteenth century was a period of rapid urban growth. Magical beliefs and practices existed at all social levels in the medieval and early modern periods, and were enmeshed in medical and scientific thought and techniques. His work has focused on the medieval and early modern periods. The life that one sacrificed to God or king in the medieval and early modern periods became, with the advent of modernity, a life offered in the name of one's country. The art forms that emerged in the early period of civilisation are primitive and catered to a people who had no alternative. The late 1950s and early 1960s were a period of expansion and creativity. The nineteenth century was a period of unparalleled imperial expansion. This strong connection between politics and music is a feature of the period. The early 1990s also was a period of persistently sluggish growth - in credit, employment and GDP. If we confine ourselves to Europe in the late medieval and early modern periods, we find that at least initial studies have been completed on England, France, Amsterdam, and parts of Germany. You said we entered a dark period in American history. The Book of Kells is one of the great masterpieces that has come down to us from a period often referred to as the Dark Ages. Economists and historians regard a reduction in real wages as one of the distinguishing features of the modern period. Also featured will be works from the Byzantine, Medieval, and Renaissance periods, as well as late 18th and early 19th century art. To be sure, the public prayer forms of the West needed culling and refining by the late medieval and early Renaissance periods. In these, information about the history of the regions and archaeological discoveries bring the Viking and early medieval periods to life. Yet the 1990s was a very robust period of growth. We have entered a critical period in financial history. Of these, 98 per cent cover the 19th and 20th centuries, while only 16 per cent cover medieval or earlier periods. Synonyms era, age, epoch, time, days, years, aeon 1.2 A major division of geological time that is a subdivision of an era and is itself subdivided into epochs, corresponding to a system in chronostratigraphy. （地质年代划分的）纪 Example sentencesExamples The event, known as the Great Dying, occurred about 250 million years ago at the boundary between the Permian and Triassic periods. Because the Miocene is closer to the present day than most other periods of geologic time, it is easier to see the effects of events, and to interpret patterns. Because of this, clay becomes progressively less common in older geological periods and is almost never found in Precambrian formations. Evolutionists say these formations represent three different geological periods ranging from 35 to 245 million years. During the Cretaceous and the Tertiary periods large parts of the present subcontinent of India were flooded by multiple lava flows. The following table shows the three eras and eleven geological periods that comprise the Phanerozoic. Geological periods are defined with reference to a Global Boundary Stratotype Section and Point. The Mesozoic era lasted from about 251 to 66 million years ago and includes the Triassic, Jurassic, and Cretaceous periods. We have additional information on the geological time periods along the top of the image. Despite our lack of knowledge, or perhaps because of it, researchers have divided the Precambrian into three time periods called eons. The extinction occurred at the boundary between the Permian and Triassic periods at a time when all land was concentrated in a supercontinent called Pangea. The Great Dying occurred between the Permian and Triassic periods, when all of today's continents were concentrated in one great land mass called Pangea. This was accompanied by the multistage emplacement of large intrusive bodies in the Cambrian, Ordovician, and Silurian periods. In contrast, dinosaur fossils have been traced in Triassic, Jurassic and Cretaceous periods. Historically, the Cenozoic has been divided up into the Quaternary and Tertiary sub-eras, as well as the Neogene and Paleogene periods. Most are restricted to one or two geologic periods, and a few contain only one genus. This book shows the dynamic effects of the many periods of Pleistocene glacial advance and melting on the geology and topography of the northwestern United States. Later geological periods show similar patterns of sudden appearance, stasis and persistent chasms of difference between major groups. The right-hand column lists the six major epochs into which the periods are divided. Extinctions have also occurred in all other periods of geological time. 1.3 One of the set divisions of the day in a school allocated to a lesson or other activity. 学时，课时 Example sentencesExamples The two of them reached the door to their first period study hall room. In my day, that meant the four boys who drank it in an alley near school during free periods (I joined them once and will spare you the details). Most of my teachers were unaware of my hours of research in the school library; the reason for this was that I was supposed to be doing something else in my free periods, so I kept quiet about what I was doing. Nothing could bring him down… until he reached his third period Algebra class. Despite the fact that this lesson took several class periods to complete, I feel it was definitely worth it. Uh, you really need to take this up next period in your Comparative Religion class. To accommodate the rich level of activity hoped for in his mathematical laboratory, he proposed that two consecutive class periods be allocated to it. Even the teacher was very interested in the argument, so she gave the class a free period. When I was looking for my third period class which is Health, the halls were really crowded. Walking down the hallway towards first period trigonometry Jordan smiled as she passed people. Teachers should also be in classrooms for all the periods allocated to them and those who served as councillors should be filled in for, he said. The total lesson takes several class periods and I recite the poems to motivate my young artists many times throughout the lesson. Youngsters coming out of school during free periods were also blamed for trouble in the town. I would look at it later and make sense of it but, as for now, I had to get to my next lesson because the free period would probably be nearing an end. My parents were a bit worried when they saw all the free periods in my timetable. I took a seat in the middle near the window in my fourth period class which was art. By the time I got to class, the first period bell was ringing. I never really got why lessons were called periods. James had a free for periods five and six, so he was in the IT room, out of the cold. Dumping her test into the inbox she left the classroom for fourth period Health. Synonyms lesson, class, session 1.4 Each of the intervals into which the playing time of a sporting event is divided. （体育比赛的）局 Example sentencesExamples There were no goals in the first period of extra time but within a minute of the restart a through-ball fell to Bowers, who made no mistake. However, with almost the last kick of the game, he scored the winning point in the fourth period of extra time. Between periods in the locker rooms, IVs drip fluids into dehydrated athletes, who eat bananas and drink even more liquids to fight off cramping. In the second period of extra time United pushed hard looking again for another equaliser. Venezuela was reduced to ten players for the second period of extra time and the pressure shifted to Uruguay. In the first period of extra time both teams played at a frenetic pace with tenacious defending keeping Keighley's hopes alive. They totally dominated the first period, scoring five and conceding one. A tense period of extra-time failed to produce a winning goal for either team. The second period of extra time saw the home side get a goal back. There have been 17 periods of extra time in European Championships and World Cups since the Golden Goal system began at Euro 96. Teams play full periods with no TV timeouts - the ultimate test of conditioning. He also missed a 30m penalty in the first period of extra time. There is an extra period called injury time, usually in the vicinity of three minutes. The match ended scoreless in normal time, but the team conceded a goal in the first period of extra time. Kinsale scored the decisive second goal three minutes into the first period of extra-time. Why is a penalty in the first period of a game in December not a penalty in the third period of a game in March? If games are tied at full-time an extra period will be played with the first team to score winning the game. They turned into gaping holes in the final period when three Belfast goals in as many minutes ended the contest. His save percentage and GAA in the third period is better than in the first two periods. But, once he scored in the sixth minute of the injury time, the script for the extra time periods could have been written. 2Physics The interval of time between successive occurrences of the same state in an oscillatory or cyclic phenomenon, such as a mechanical vibration, an alternating current, a variable star, or an electromagnetic wave. 〔物理〕（振动或循环的）周期 Example sentencesExamples To produce a larger effect, the motion must accumulate, and for wave-impulses to accumulate, they must arrive in periods identical with the periods of vibration of the atoms on which they impinge. 2.1Astronomy The time taken by a celestial object to rotate around its axis, or to make one circuit of its orbit. 〔天文〕自转（或公转）周期 Example sentencesExamples The atmosphere rotates with periods ranging from over 18 hours near the equator to faster than 13 hours near the poles. The first problem Galileo attacked at Florence was to determine orbits and periods for Jupiter's four satellites. Certainly the book would be more compelling if it contained a success story on a par with accounting for the periods of the planetary orbits or the perihelion shift of Mercury. Typical distances from the Sun are 10,000 astronomical units, and typical orbital periods are on the order of 1 million years. In contrast, Jupiter-family comets tend to have predictable, well-determined orbits with short periods and low inclinations. 2.2Mathematics The interval between successive equal values of a periodic function. 〔数〕（周期函数的）周期 Example sentencesExamples What is the period of the continued fractions of the following numbers? In 1834 Jacobi proved that if a single-valued function of one variable is doubly periodic then the ratio of the periods is imaginary. 3A flow of blood and other material from the lining of the uterus, lasting for several days and occurring in sexually mature women who are not pregnant at intervals of about one lunar month until the onset of menopause. （妇女的）经期 Example sentencesExamples Three standard gynecological texts state that the commonly observed interval between menstrual periods is 26 to 30 days, 24 to 32 days, and 24 to 35 days. If a woman does not have periods (due to menopause or removal of uterus), then it may be done on a fixed day of the month. It affects women much more often than men, because women lose some blood in each menstrual period between puberty and the menopause. During puberty or nearing menopause, many women have irregular periods so no treatment is necessary. Women who receive chemotherapy may have a change in their periods or menstrual cycles. Some older women think the absence of periods is related to menopause and not pregnancy. It mostly affects women between the ages of 50 and 70, who have been through the menopause (when your periods stop). Sometimes the cause is clear, for example in women who are pregnant or have heavy periods. You then need to use progesterone pessaries until your periods start again. Amenorrhea just means an absence of menstrual cycles or periods for at least about three to six months, and the particular type of amenorrhea that we were studying is called hypothalamic. Because sex during menstruation may increase the chances of transmitting or contracting HIV, it may be safer for women to wait until their periods are over to have sex. During early pregnancy, some women develop acne, especially those who were prone to breakouts during menstrual periods before becoming pregnant. A headache diary may be necessary to confirm the relationship between migraine and menstruation, especially if periods are irregular. Amenorrhoea is the absence of periods (menstruation). Most women have some crampy pain with their periods, especially as teenagers. Many women don't suspect they're pregnant until their period doesn't arrive. About 60% of women who say they have heavy periods are found to have normal periods when their blood loss is measured. Women may also experience painful periods and pain during sexual intercourse. It is common to have heavy blood flow at the beginning of a period and lighter blood flow at the end. Examples include when a partner leaves, pregnancies among very young women, those with irregular periods or at the menopause, or when testing has shown a baby with abnormalities. Synonyms menstruation, menstrual flow 4North American A punctuation mark (.) used at the end of a sentence or an abbreviation. British term full stop Example sentencesExamples He put a period on the end of the last sentence, and placed the pen down with a loud sound and looked up at her. Small pauses were commas, larger ones were semicolons and colon; and periods of course were the longest pause of all. The dependent clause following the first period appears to be a sentence fragment. A name is nothing but two proper nouns with a letter and a period stuck between them. The first sentence should have been ended with a period and not a question mark. There are two periods at the end of the last sentence in the first testimonial. These marks are very small indeed, about the size of a period at the end of a sentence. As you could guess, exclamation points outnumbered periods in her story. Simple input issues such as periods or abbreviations would make older databases think it was a new entry. He often ended interrogatives with periods. We use American punctuation standards - put your commas and periods inside your quotation marks. The dominant American style is to include commas and periods within quotation marks even when that punctuation doesn't belong to the quotation. As he talked he jabbed the lit end of his cigar into the air as though he were punctuating his sentences by burning periods in the air. Synonyms full stop, full point, point, stop 4.1informal Added to the end of a statement to indicate that no further discussion is possible or desirable. 〈非正式〉到此为止，就这样（常用于陈述末尾，表示无法或无需再讨论） he is the sole owner of the trademark, period 他是那商标的唯一所有人，就是这样。 Example sentencesExamples "You hate cats period, " Tiffany reminded her fondly. He could simply have said he favours public ownership, full stop, period. Synonyms and that's that, and that is the end of the matter, full stop, finis 5Chemistry A set of elements occupying an entire horizontal row in the periodic table. 〔化〕周期元素 Example sentencesExamples As we move down the periods, the elements have a greater atomic weight. The horizontal rows or periods also have predictable trends in characteristics because as you move left to right in a row only one electron is added changing the atomic number by one. 6Rhetoric A complex sentence, especially one consisting of several clauses, constructed as part of a formal speech or oration. 〔修辞〕完整句 Example sentencesExamples There is frequently poor closure of periods and an inept employment of rhythm in the closure of stanzas and of poems. 6.1Music A complete idea, typically consisting of two or four phrases. 〔乐〕乐段，乐节 Example sentencesExamples His's an oceanic performance that gives emphasis to the work's undulating hemiolas as they reach across bar lines and destabilize phrase periods. adjectiveˈpɪriədˈpirēəd attributive Belonging to or characteristic of a past historical time, especially in style or design. （尤指风格或设计）属于过去某一特定历史时期的；具有过去某一特定历史时期特点的 a splendid selection of period furniture 古老家具精选。 Example sentencesExamples The houses would need to be empty and if they have period furniture and furnishings that would be an extra advantage. The owners of one of the most important period houses in Cork are to cut their losses after a bitter planning saga. At the first event some people were unsure about dressing up in period costume. We are in the early 1970s, with plenty of gleaming period automobiles rolling past on cue. They are furnished in period style and presented to the public as representative of a national or regional cultural tradition. A home that has both period style and modern comforts - is it perfection? He said that period houses of this type and location were among some of the most popular in the city. This old period house and shop front set beside the bridge and River Moy has a mystique all of its own. The hotel's 64 rooms are in comfortable period style, with heavy doors and lots of antiques and arches. This stylishly renovated period lodge has been designed to take full advantage of the mature front garden. The walls are painted in a soft cream colour and there are period style fireplaces at either end. This house is a great blend of period qualities and contemporary design. The room is furnished with expensive period furniture and even an antique gramophone. However, although much work was needed, care was taken to preserve the period style of the mansion. First performed in 1948, it is interesting today only as a period piece. The anniversary of a momentous battle fought only a few miles from York has been marked in period style. Some town councillors donned period costume to add to the authenticity of the celebrations. There are eight suites - all decorated by Patricia with French period furniture. One of the highlights of the weekend will be period re-enactments of historical trials in the old Law Courts in City Hall. Each of the five apartments is spacious and well-equipped and decorated in period style. Synonyms in period style, period, nostalgic, evocative, of yesteryear, olde worlde Origin Late Middle English (denoting the time during which something, especially a disease, runs its course): from Old French periode, via Latin from Greek periodos ‘orbit, recurrence, course’, from peri- ‘around’ + hodos ‘way, course’. The sense ‘portion of time’ dates from the early 17th century.
随便看	fit-up fit up fit up fitzgerald Fitzgerald, Barry FitzGerald contraction Fitzgerald, Edward Fitzgerald, Ella Fitzgerald, F. Scott fitzgerald, f scott fitzgerald-lorentz contraction fitzgeralds FitzGerald–Lorentz contraction Fitzrovia Fitzroy Fiume five five a day five a day five-alarm five-and-dime five-and-dime store five-and-ten five-a-side five-a-sides