equinox

e·qui·nox  (kw-nks, kw-) n. 1. Either of two points on the celestial sphere at which the ecliptic intersects the celestial equator. 2. Either of the two times during a year when the sun crosses the celestial equator and when the length of day and night are approximately equal; the vernal equinox or the autumnal equinox. [Middle English, from Old French equinoxe, from Medieval Latin aequinoxium, from Latin aequinoctium : aequi-, equi- + nox, noct-, night; see nekw-t- in Indo-European roots.]

equinox celestial sphere showing the positions of the autumnal and vernal equinoxes

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equinox [ˈiːkwɪˌnɒks ˈɛkwɪˌnɒks]

n

1. (Astronomy) either of the two occasions, six months apart, when day and night are of equal length See vernal equinox, autumnal equinox

2. (Astronomy) another name for equinoctial point

[from Medieval Latin equinoxium, changed from Latin aequinoctium, from aequi- equi- + nox night]

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equinox  (kw-nks)

1. Either of the two points on the celestial sphere where the ecliptic (the apparent path of the Sun) crosses the celestial equator. The point at which the Sun's path crosses the celestial equator moving from south to north is called the vernal equinox. The vernal equinox marks the zero point in both the equatorial and ecliptic coordinate systems; horizontal angular distances (right ascension in the equatorial system and celestial longitude in the ecliptic system) are measured eastward from this point. The vernal equinox is also known as the first point of Aries because when first devised some 2,000 years ago this point occurred at the beginning of Aries in the zodiac. Because of the westward precession of the equinoxes, the vernal equinox is now located at the beginning of Pisces. The point at which the Sun's path crosses the celestial equator moving from north to south is called the autumnal equinox.

2. Either of the two corresponding moments of the year when the Sun is directly above the Earth's equator. The vernal equinox occurs on March 20 or 21 and the autumnal equinox on September 22 or 23, marking the beginning of spring and autumn, respectively, in the Northern Hemisphere (and the reverse in the Southern Hemisphere). The days on which an equinox falls have about equal periods of sunlight and darkness. Compare solstice.

Thesaurus

Noun	1.	equinox - 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 cosmic time - the time covered by the physical formation and development of the universe March equinox, spring equinox, vernal equinox - March 21 autumnal equinox, fall equinox, September equinox - September 22
	2.	equinox - (astronomy) either of the two celestial points at which the celestial equator intersects the ecliptic equinoctial point astronomy, uranology - the branch of physics that studies celestial bodies and the universe as a whole celestial point - a point in the heavens (on the celestial sphere) vernal equinox - (astronomy) the equinoctial point that lies in the constellation of Pisces autumnal equinox - (astronomy) the equinoctial point that lies in the constellation of Virgo

Translations

equinox [ˈiːkwɪnɒks] N → equinoccio m

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equinox [ˈiːkwinɒks ˈɛkwinɒks] n → équinoxe m spring equinox, autumn equinox

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equinox

n → Tagundnachtgleiche f, → Äquinoktium nt; the spring/autumn equinox → die Frühjahrs-/Herbst-Tagundnachtgleiche

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equinox [ˈiːkwɪnɒks] n → equinozio

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equinox [ˈiːkwɪnɒks] n → equinozio

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equinox

n equinox [ˈekwinoks]

the time when the sun crosses the equator, about March 21 and September 23. nagewening, dag-en-nag-ewening, nageweningspunt الإعْتِدال الرَّبيعي أو الخَريفي равноденствие rovnodennost jævndøgn die Tag– und Nachtgleiche ισημερία equinoccio võrdpäevsus اعتدالین؛ برابری شب و روز päiväntasaus équinoxe שִׁוויוֹן הַיוֹם וְהַלַילָה विषुव ekvinocij napéjegyenlőség ekuinoks jafndægur equinozio 春 [] 分 주야 평분시 ekvinokcija ekvinokcija ekuinoks nachtevening jevndøgn zrównanie dnia z nocą equinócio echinox равноденствие rovnodennosť enakonočje ravnodnevnica dagjämning ช่วงที่เวลาในตอนกลางวันและกลางคืนเท่ากัน ซึ่งมักจะเกิดในช่วงวันที่ 21 มีนาคมและ 23 กันยายน gün-tün eşitliği 晝夜平分時春/秋分點 рівнодення وہ وقت یا تاریخ جب سورج اپنے استواے سماوی کو قطع کرتا ہے điểm phân 昼夜平分时春（秋）分点