(1):

(a.) Present; current.

(2):

(a.) Closely pressing or impending in respect to time; not deferred; immediate; without delay.

(3):

(adv.) Instantly.

(4):

(a.) A point in duration; a moment; a portion of time too short to be estimated; also, any particular moment.

(5):

(a.) A day of the present or current month; as, the sixth instant; - an elliptical expression equivalent to the sixth of the month instant, i. e., the current month. See Instant, a., 3.

(6):

(a.) Pressing; urgent; importunate; earnest.