/ee'kweuh nok"sheuhl, ek'weuh-/ , adj.
1. pertaining to an equinox or the equinoxes, or to the equality of day and night.
2. pertaining to the celestial equator.
3. occurring at or about the time of an equinox.
4. Bot. (of a flower) opening regularly at a certain hour.
n.
5. See celestial equator .
6. See equinoctial storm .
[ 1350-1400; ME aequinoctialis pertaining to the equinox. See EQUINOX, -AL 1 ]