Definition of autumnal equinox in English:

autumnal equinox

(also autumn equinox)

See synonyms for autumnal equinox

noun

  • 1The equinox in autumn, on about September 22 in the northern hemisphere and March 20 in the southern hemisphere.

    ‘Sunlight is continuous throughout the summer, but after the solstice the sun slowly sinks to the horizon until it drops below on the autumn equinox.’
    • ‘The autumn equinox was 22nd September but I'll be celebrating it with friends and family today.’
    • ‘Make a portrait of the north woods in upper Minnesota over the ninety days between the autumn equinox and winter solstice.’
    • ‘The Council will be held at the autumn equinox in a few weeks from now.’
    • ‘Thus, Libra is Libra because it comes in the autumn equinox, when the Sun spreads its light equally over both hemispheres.’
    • ‘They are seasonal visitors which migrate to warmer waters when the days get shorter after the autumn equinox.’
    • ‘He disappeared off Iceland in the storms of the autumn equinox of 1942, poor chap.’
    • ‘The Sun only sets precisely due west on the day of the spring or autumn equinox.’
    • ‘The autumnal equinox occurs in March in the Southern Hemisphere, and the spring equinox occurs in September.’
    • ‘The equal light and dark provides the scientific term for the beginning of fall - the autumnal equinox in the Northern Hemisphere.’
    • ‘The autumnal equinox occurs on September 22 at 1: 27 P.M., when Earth reaches a position in its orbit that brings the Southern Hemisphere closer to the Sun.’
    • ‘That full Moon is known as the harvest Moon: the full Moon closest to the autumnal equinox in the Northern Hemisphere.’
    • ‘In ancient Egypt and Persia New Year began on September 21, at the autumnal equinox, when day and night were of equal length.’
    • ‘The autumnal equinox was more than a month ago on September 23 and we are just 56 days short of the shortest day which falls on December 22.’
    • ‘Similarly, the autumnal equinox and winter solstice represent the astronomical beginnings of autumn and winter.’
    • ‘In ancient times, fasts were traditional at the vernal and autumnal equinoxes and were believed to increase fertility.’
    • ‘At the autumnal equinox, we celebrate last harvest, or Mabon.’
    • ‘On a brilliant early morning of the autumnal equinox, Rose and I made our way down to the banks of a nearby river where we read letters of commitment to each other.’
    • ‘Although it marks the autumnal equinox here, it is still a good time for tree planting and a time of vigorous growth.’
    • ‘In the plate's center is a representation of the star cluster Pleiades, which appears in the sky around the autumnal equinox and signaled the arrival of harvest season.’
    1. 1.1Astronomy The equinox in September, when the sun crosses the celestial equator in a southerly direction.