a very brief period of time; a second

a precise point in time, esp separating two states

at the instant of death

formal, dated used in business correspondence: the present or current month: compare proximo, ultimo

immediate

an instant success

of food: premixed, precooked, or otherwise prepared for easy use or application

appearing in or as if in ready-to-use form

updating your image with instant beards, moustaches, and sideburns — Playboy

formal demanding or urgent