Entry 6 senses · 3 variants Webster, 1913

Instant

/ĭn'-stənt/ · In·stant · IPA /ˈɪnstənt/

01 a. Pressing; urgent; importunate; earnest.

1.
Pressing; urgent; importunate; earnest.
“Rejoicing in hope; patient in tribulation; continuing instant in prayer.” — Rom. xii. 12.

“I am beginning to be very instant for some sort of occupation.” — Carlyle.
2.
Closely pressing or impending in respect to time; not deferred; immediate; without delay.
“Impending death is thine, and instant doom.” — Prior.
3.
Present; current.
“The instant time is always the fittest time.” — Fuller.

02 adv. Instantly.

1.
Instantly.[Poetic]
“Instant he flew with hospitable haste.” — Pope.

03 n. A point in time; a moment; a portion of time too short to be estimated; also, any particular moment; as, the situation may change in an instant.

1.
A point in time; a moment; a portion of time too short to be estimated; also, any particular moment; as, the situation may change in an instant.
“There is scarce an instant between their flourishing and their not being.” — Hooker.
2.
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. See: Instant

Syn. Moment; flash; second.