An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

The season of the year between summer and winter; it begins in the northern hemisphere at the → autumnal equinox and ends at the → winter solstice.

O.Fr., from L. autumnus, a word probably of Etruscan origin.

Pâyiz, from Mid.Pers. pâdiz or pâtez, from Proto-Iranian *pâti-z(a)ya- "near winter," from pâti "near" + *z(a)ya- "winter," compare with Av. zyan- or zyam- "winter" (Skt. heman, Gk. xeimon, L. hiems).

→ autumnal equinox.

→ autumn; → equinox.

One of the two points where the → ecliptic crosses the → celestial equator. At the autumnal equinox the Sun appears to be moving across the equator from the northern celestial hemisphere to the southern celestial hemisphere. The instant of the event.

→ autumn; → -al; → equinox.