at one time in the past; formerly: I was a farmer once;a once powerful nation.
a single time: We ate there just once.We go to a movie once a week.
even a single time; at any time; ever: If the facts once become known, it will be just too bad.
by a single step, degree, or grade: a cousin once removed.
adjective
former; having at one time been: the once and future king.
conjunction
if or when at any time; if ever.
whenever; as soon as: Once you're finished, you can leave.
noun
a single occasion; one time only: Once is enough.
Idioms for once
all at once,
simultaneously: The children were running, screaming, and throwing things all at once.
suddenly: All at once the rain came down.
at once,
at the same time; simultaneously: Don't all speak at once.
immediately; promptly: Tell him to come at once!
once and again, repeatedly: He has been told once and again not to slam the door.
once and for all, decisively; finally: Let's settle this problem once and for all.Also once for all.
once in a while, at intervals; occasionally: She stops in to see us once in a while.
once or twice, a very few times; infrequently: I've seen her in the elevator once or twice.
once upon a time, at some unspecified past time, especially a long time ago: Once upon a time, in a faraway land, there lived a prince and princess.
Origin of once
First recorded before 1150; Middle English ones, Old English ānes, originally genitive of ān “one” replacing Middle English enes, Old English ǣnes “once,” equivalent to ǣne “once” (originally instrumental of ān ) + -es adverb suffix; see one, -s1
Words nearby once
onboard, on borrowed time, live, ONC, on call, on-camera, once, once and for all, Once bitten, twice shy, once in a blue moon, once in a lifetime, once in a while
already, formerly, previously, earlier, late, before, erstwhile, back, bygone, heretofore, old, one, sometime, quondam, at one time, long ago, once upon a time, time was, whilom