equinox

English · Thesaurus

AI In plain words

Writing a short explanation…

Written by a house AI from the entry below, in your language. The entry itself is the source.

equinox

/ˈɛkwɪnɒks/ UK
/ˈiː-/ UK
/ˈɛkwəˌnɑks/ US
/ˈi-/ US
/ˈɛkwɪˌnɑks/ Canada
/ˈiː-/ Canada
/ˌɛkwɪˈnɒktiːz/ UK
/ˌiː-/ UK
/ˌɛkwəˈnɑktiz/ US
/ˌi-/ US
/ˌɛkwɪˈnɑktiz/ Canada
/ˌi-/ Canada

Where it comes from

PIE word

*nókʷts

From Middle English equinox, equinoxe, equynox (“one of the two periods in the year when the day and night are of equal length, equinox; either the zodiac sign Aries or Libra, in which the sun crosses the celestial equator”), from Old French equinoce, equinoxe (modern French équinoxe), or from its etymon Medieval Latin ēquinoxium, ēquinoctium, from Latin aequinoctium (“equinox”), from aequus (“equal”) + nox (“night”) (ultimately derived from Proto-Indo-European *nókʷts (“night”)) + -ium (suffix forming abstract nouns). The Latin word, ultimately adopted in Middle English and modern English, displaced Old English efnniht (modern English evennight).

The rare alternative plural form equinoctes treats equinox as if it were a Latin word; the plural of Latin nox (“night”) is noctēs.

noun equinoxes · equinoctes · æquinox

One of two times in the year (one in March and the other in September) when the length of the day and the night are equal, which occurs when the sun is directly overhead at the equator; this marks the beginning of spring in one hemisphere and autumn in the other. [T]he Months of March and September, the tvvo Æquinoxes of Our year, are the moſt vvindy and tempeſtuous, the moſt unſettled and unequable of Seaſons in moſt Countries of the VVorld.
Similar: evennight
also, figuratively The circumstance of a twenty-four hour time period having the day and night of equal length. [D]oe but ſee his vice, / Tis to his vertue, a iuſt equinox, / The one as long as th'other: […]
One of the two points in space where the apparent path of the Sun intersects with the equatorial plane of the Earth.
obsolete, rare A gale (“very strong wind”) once thought to occur more frequently around the time of an equinox (sense 1), now known to be a misconception; an equinoctial gale. The paſſage yet vvas good, the vvind, 'tis true, / VVas ſomevvhat high, but that vvas nothing nevv, / Nor more than uſual Equinoxes blevv.
obsolete A celestial equator (“great circle on the celestial sphere, coincident with the plane of the Earth's equator (the equatorial plane)”); also, the Earth's equator. [T]hey [seals] are over all the American Coaſt of the South Seas, from Terra del Fuego, up to the Equinoctial Line: but to the North of the Equinox again, in theſe Sea, I never ſavv any, till as far as 21 North Lat[itude].
Similar: equinoctial line

Thesaurus

Closest in meaning: equinoctial point, autumnal, vernal, equinoxe, march equinox, autumnal equinox, september equinox, vernal equinox, southward equinox, northward equinox, fall equinox, spring equinox, autumn equinox, equinoctial colure, equinoxial, solstice

Translations

Every language

noun one of the two times in the year when the length of the day and night are equal, which occurs when the apparent path of the Sun intersects with the equatorial p

Español	equinoccio
한국어	분점 bunjeom
日本語	分点 bunten
中文	二分點 /二分点 èrfēndiǎn, 分點 /分点 fēndiǎn, 晝夜平分點 /昼夜平分点 zhòuyè píngfēndiǎn
हिन्दी	विषुव viṣuv
Kiswahili	ikwinoksi, sikusare
Português	equinócio
Français	équinoxe
Deutsch	Äquinoktium, Tagnachtgleiche, Tagundnachtgleiche
Italiano	equinozio
Ελληνικά	ισημερία isimería
Română	echinox, echinocțiu
Русский	равноде́нствие ravnodénstvije
Tiếng Việt	điểm phân
العربية	اِعْتِدَال iʕtidāl
עברית	נקודת השוויון

Talk about this word

Cite this

MLA

"equinox." Wiktionary, via Micwyn, micwyn.com/word/equinox. Accessed 6 Nov. 2026.

APA

equinox. (n.d.). In Wiktionary, via Micwyn. Retrieved November 6, 2026, from https://micwyn.com/word/equinox

Chicago

"equinox." Wiktionary, via Micwyn. Accessed November 6, 2026. https://micwyn.com/word/equinox.

BibTeX

@misc{equinox_2026,
  title = {equinox},
  howpublished = {Wiktionary, via Micwyn},
  year = {2026},
  url = {https://micwyn.com/word/equinox},
  urldate = {2026-11-06}
}