Definition of noctilucent cloud in English:

noctilucent cloud

nounˌnɒktɪˈluːs(ə)ntnäktəˌlo͞os(ə)nt ˈkloud

A luminous cloud of a kind occasionally seen at night in summer in high latitudes, at the altitude of the mesopause.
夜光云
he estimated the height of the noctilucent clouds he saw at 80 to 100 km
Example sentencesExamples
- Other terms related to the sky and atmosphere are southern aurora, noctilucent clouds, and one which is now generally familiar, the ozone hole, first noted by British Antarctic Survey scientists working in Antarctica.
- Evidence of these changes comes from sightings of noctilucent clouds, very unusual clouds seen only in polar regions and known to be in the mesosphere.
- At these times the clouds are visible and are therefore referred to as noctilucent clouds.
- One of them is something that I've never actually seen but I had seen pictures of; it's a thing called a noctilucent cloud, this is a cloud that occurs at about 86 kilometres, it may be present more often than we see it.
- ‘Humbug’ refers to natural phenomena such as heavenly bodies, noctilucent clouds, ball lightning, and man-made objects such as glowing blimps.

Origin

Late 19th century: from Latin nox, noct- 'night' + lucere 'to shine' + -ent.

Definition of noctilucent cloud in US English:

noctilucent cloud

nounnäktəˌlo͞os(ə)nt ˈkloud

A high-altitude cloud that is luminous at night, especially in summer in high latitudes.
he estimated the height of the noctilucent clouds he saw at 80 to 100 km
Example sentencesExamples
- Other terms related to the sky and atmosphere are southern aurora, noctilucent clouds, and one which is now generally familiar, the ozone hole, first noted by British Antarctic Survey scientists working in Antarctica.
- At these times the clouds are visible and are therefore referred to as noctilucent clouds.
- ‘Humbug’ refers to natural phenomena such as heavenly bodies, noctilucent clouds, ball lightning, and man-made objects such as glowing blimps.
- Evidence of these changes comes from sightings of noctilucent clouds, very unusual clouds seen only in polar regions and known to be in the mesosphere.
- One of them is something that I've never actually seen but I had seen pictures of; it's a thing called a noctilucent cloud, this is a cloud that occurs at about 86 kilometres, it may be present more often than we see it.

Origin

Late 19th century: from Latin nox, noct- ‘night’ + lucere ‘to shine’ + -ent.

词汇	noctilucent cloud
释义	Definition of noctilucent cloud in English: noctilucent cloud nounˌnɒktɪˈluːs(ə)ntnäktəˌlo͞os(ə)nt ˈkloud A luminous cloud of a kind occasionally seen at night in summer in high latitudes, at the altitude of the mesopause. 夜光云 he estimated the height of the noctilucent clouds he saw at 80 to 100 km Example sentencesExamples Other terms related to the sky and atmosphere are southern aurora, noctilucent clouds, and one which is now generally familiar, the ozone hole, first noted by British Antarctic Survey scientists working in Antarctica. Evidence of these changes comes from sightings of noctilucent clouds, very unusual clouds seen only in polar regions and known to be in the mesosphere. At these times the clouds are visible and are therefore referred to as noctilucent clouds. One of them is something that I've never actually seen but I had seen pictures of; it's a thing called a noctilucent cloud, this is a cloud that occurs at about 86 kilometres, it may be present more often than we see it. ‘Humbug’ refers to natural phenomena such as heavenly bodies, noctilucent clouds, ball lightning, and man-made objects such as glowing blimps. Origin Late 19th century: from Latin nox, noct- 'night' + lucere 'to shine' + -ent. Definition of noctilucent cloud in US English: noctilucent cloud nounnäktəˌlo͞os(ə)nt ˈkloud A high-altitude cloud that is luminous at night, especially in summer in high latitudes. he estimated the height of the noctilucent clouds he saw at 80 to 100 km Example sentencesExamples Other terms related to the sky and atmosphere are southern aurora, noctilucent clouds, and one which is now generally familiar, the ozone hole, first noted by British Antarctic Survey scientists working in Antarctica. At these times the clouds are visible and are therefore referred to as noctilucent clouds. ‘Humbug’ refers to natural phenomena such as heavenly bodies, noctilucent clouds, ball lightning, and man-made objects such as glowing blimps. Evidence of these changes comes from sightings of noctilucent clouds, very unusual clouds seen only in polar regions and known to be in the mesosphere. One of them is something that I've never actually seen but I had seen pictures of; it's a thing called a noctilucent cloud, this is a cloud that occurs at about 86 kilometres, it may be present more often than we see it. Origin Late 19th century: from Latin nox, noct- ‘night’ + lucere ‘to shine’ + -ent.
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