adv., conj., & n.
--adv.
1. on one occasion or for one time only (did not once say please; have read it once).
2 at some point or period in the past (could once play chess).
3 ever or at all (if you once forget it).
4 multiplied by one; by one degree.
--conj. as soon as (once they have gone we can relax).
--n. one time or occasion (just the once).
Phrases and idioms:
all at once 1 without warning; suddenly.
2 all together. at once 1 immediately.
2 simultaneously. for once on this (or that) occasion, even if at no other. once again (or more) another time. once and for all (or once for all) (done) in a final or conclusive manner, esp. so as to end hesitation or uncertainty. once (or every once) in a while from time to time; occasionally. once or twice a few times. once-over colloq. a rapid preliminary inspection or piece of work. once upon a time at some vague time in the past.
Etymology: ME anes, ones, genit. of ONE