| 释义 |
Definition of equant in English: equantnoun ˈiːkwəntˈēkwənt Astronomy historical (in the Ptolemaic system) an imaginary circle introduced with the purpose of reconciling the planetary movements with the hypothesis of uniform circular motion. 〔天文〕〈史〉（托勒密体系所说的）均轮 Example sentencesExamples - When the intricacies of epicycles, deferents and equants were explained to him Alfonso ‘the Wise’ is said to have remarked that if the Almighty had consulted him on the matter, he would have recommended something a little simpler…
- But Ptolemy was not trying, when he devised the equant, to offer a mechanical account of why the planets moved as they did.
- If you had asked Aristotle or Ptolemy to explain how planets move, you would have got a lecture on epicycles and equants.
- Gingerich noted ‘the majority of sixteenth-century astronomers thought eliminating the equant was Copernicus' big achievement.’
- While the epicycle is moving at a uniform rate with respect to the equant, it does not move at a uniform rate with respect to the centre of the deferent or even with respect to the Earth.
adjective ˈiːkwəntˈēkwənt Geology (of a crystal or particle) having its different diameters approximately equal, so as to be roughly cubic or spherical in shape. 〔地质〕（晶体，粒子）等径的 Example sentencesExamples - A few outstanding composite specimens were recovered, with crude dendritic copper intergrown with one or two large, single, equant crystals.
- This large (about 5 meters in diameter) equant vein has a distinct concentric zonation.
- Doubly terminated, transparent, colorless equant crystals of classic Herkimer ‘diamond’ habit are locally common.
- It typically occurs as transparent flattened crystals, as small equant crystals, as intergrown masses of small lustrous crystals, and occasionally as stout or elongated twinned crystals.
- Both samples consist of fine-grained calcite with elongated or equant shapes.
OriginMid 16th century: from Latin aequant- 'making equal', from the verb aequare. Definition of equant in US English: equantnounˈēkwənt Astronomy historical (in the Ptolemaic system) an imaginary circle introduced with the purpose of reconciling the planetary movements with the hypothesis of uniform circular motion. 〔天文〕〈史〉（托勒密体系所说的）均轮 Example sentencesExamples - But Ptolemy was not trying, when he devised the equant, to offer a mechanical account of why the planets moved as they did.
- Gingerich noted ‘the majority of sixteenth-century astronomers thought eliminating the equant was Copernicus' big achievement.’
- When the intricacies of epicycles, deferents and equants were explained to him Alfonso ‘the Wise’ is said to have remarked that if the Almighty had consulted him on the matter, he would have recommended something a little simpler…
- If you had asked Aristotle or Ptolemy to explain how planets move, you would have got a lecture on epicycles and equants.
- While the epicycle is moving at a uniform rate with respect to the equant, it does not move at a uniform rate with respect to the centre of the deferent or even with respect to the Earth.
adjectiveˈēkwənt Geology (of a crystal or particle) having its different diameters approximately equal, so as to be roughly cubic or spherical in shape. 〔地质〕（晶体，粒子）等径的 Example sentencesExamples - Both samples consist of fine-grained calcite with elongated or equant shapes.
- It typically occurs as transparent flattened crystals, as small equant crystals, as intergrown masses of small lustrous crystals, and occasionally as stout or elongated twinned crystals.
- Doubly terminated, transparent, colorless equant crystals of classic Herkimer ‘diamond’ habit are locally common.
- This large (about 5 meters in diameter) equant vein has a distinct concentric zonation.
- A few outstanding composite specimens were recovered, with crude dendritic copper intergrown with one or two large, single, equant crystals.
OriginMid 16th century: from Latin aequant- ‘making equal’, from the verb aequare. |