autumnal equinox

[ aw-tuhm-nl ee-kwuh-noks, ek-wuh-noks ]

noun

1. equinox1
2. Also called autumnal point. the position of the sun at the time of the autumnal equinox.

autumnal equinox

noun

1. the time at which the sun crosses the plane of the equator away from the relevant hemisphere, making day and night of equal length. It occurs about Sept 23 in the N hemisphere (March 21 in the S hemisphere)
2. astronomy
   1. the point, lying in the constellation Virgo, at which the sun's ecliptic intersects the celestial equator
   2. the time at which this occurs as the sun travels north to south (23 September)

autumnal equinox

/ ô-tŭm′nəl /

1. See under equinox

Word History and Origins

Origin of autumnal equinox¹

First recorded in 1670–80

Example Sentences

As Jupiter's northern hemisphere was passing through its autumnal equinox, they concluded they had landed exactly at the pole.

From Project Gutenberg

The summer had now passed, and the autumnal equinox was rapidly approaching.

From Project Gutenberg

The autumnal equinox day came round, and the monster ate nothing.

From Project Gutenberg

At the vernal and at the autumnal equinox I take a good meal, and that lasts me for half a year.

From Project Gutenberg

They call this autumnal equinox the beginning of the civil year, and the vernal equinox the beginning of the holy year.

From Project Gutenberg