equinox
ˈɛkwɪnɒks
ˈiːkwɪnɒks
noun
the time or date (twice each year) at which the sun crosses the celestial equator, when day and night are of approximately equal length (about 22 September and 20 March).
noun
the time or date (twice each year) at which the sun crosses the celestial equator, when day and night are of approximately equal length (about 22 September and 20 March).