Definition of instant

• a. - Pressing; urgent; importunate; earnest.
• a. - Closely pressing or impending in respect to time; not deferred; immediate; without delay.
• a. - Present; current.
• adv. - Instantly.
• a. - A point in duration; a moment; a portion of time too short to be estimated; also, any particular moment.
• 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.