1. [syn: autumnal equinox, September equinox, fall equinox]
2. (astronomy) the equinoctial point that lies in the constellation of Virgo;
The Collaborative International Dictionary of English v.0.48:
Autumnal \Au*tum"nal\, a. [L. auctumnalis, autumnalis: cf. F.
1. Of, belonging to, or peculiar to, autumn; as, an autumnal
tint; produced or gathered in autumn; as, autumnal fruits;
flowering in autumn; as, an autumnal plant.
Thick as autumnal leaves that strow the brooks
In Vallombrosa. --Milton.
2. Past the middle of life; in the third stage.
An autumnal matron. --Hawthorne.
Autumnal equinox, the time when the sun crosses the
equator, as it proceeds southward, or when it passes the
Autumnal point, the point of the equator intersected by the
ecliptic, as the sun proceeds southward; the first point
Autumnal signs, the signs Libra, Scorpio, and Sagittarius,
through which the sun passes between the autumnal equinox
and winter solstice.
WordNet (r) 3.0 (2006):
n 1: September 22 [syn: autumnal equinox, September equinox,
fall equinox] [ant: March equinox, spring equinox,
2: (astronomy) the equinoctial point that lies in the
constellation of Virgo