Dictionary.net

Equinoctial wind or storm.

Equinoctial wind or storm.

The time when the sun crosses the equator of the sky: about March 21 and September 22.

The precise time when the sun enters one of the equinoctial points, or the first point of Aries, about the 21st of March, and the first point of Libra, about the 23d of September, making the day and the night of equal length; these are called respectively the vernal and autumnal equinoxes: equinoctial gale. anything equal; an equal measure (rare).

Time when the sun crosses the equator, and day and night are equal.

One of two points at which the sun crosses the equator, when the days and nights are equal; also, the time of this crossing (about Mar. 21 and Sept. 22).

The precise time when the sun enters one of the equinoctial points, making the day and the night of equal length, the first point of Aries about the 21st of March, and the first point of Libra about the 23rd of September, which are severally called the vernal and the autumnal equinoxes. See Precession.

The time when the sun enters on the equinoctial line-the sun rising higher in the heavens every day at noon till the point is reached when the days and nights are of equal length all over the world, makes what is called the vernal or spring equinox, about 21st March; when the same point is reached in descending, the sun makes what is called the autumnal equinox, about 23d September.

n. [Latin] The precise time when the sun enters one of the equinoctial points.

Equinoxes are the precise times in which the sun enters into the first point of Aries and Libra; for then, moving exactly under the equinoctial, he makes our days and nights equal; equinoctial wind.