equinox

Từ điển WordNet v3.1 - WordNet Dictionary

noun

1. either of two times of the year when the sun crosses the plane of the earth's equator and day and night are of equal length
• Derivationally related forms:
equinoctial
• Hypernyms:
cosmic time
• Hyponyms:
vernal equinox, March equinox, spring equinox, autumnal equinox, September equinox, fall equinox
2. (astronomy) either of the two celestial points at which the celestial equator intersects the ecliptic
• Syn:
equinoctial point
• Topics:
astronomy, uranology
• Hypernyms:
celestial point
• Hyponyms:
vernal equinox, autumnal equinox