Synonyms for Once:
adv.•in the past; occurred one time only (adverb)
already, earlier, before, once only, one, previously.
n.beyond, after, Since, subsequently, following, in the course of time, in time, ensuing, succeeding, subsequent. ago, uniquely, once only, one day. earlier, Aforetime, one shot, already, unrepeatable, isolated, before, in/at one fell swoop, precede, Beforetime, once in a lifetime, previously, one-off. •formerly (noun)
•one time (noun)