88 entries under adverb topic. ×

7
in the past(verb, expression, idiom, phrasal verb)
7
occasionally(expression, time, moment, period)
6
on one occasion(expression, adjective, idiom, past)
6
whilom(adjective, past, precede)
5
after(conjunction, immediately, when)
5
bygone(adjective, last, original, late)
5
ever
5
hitherto
5
time
5
time was(expression, adjective, late, old)
4
back(adjective, late, past, earlier)
4
erst
4
on occasion(expression, time, moment, period)
4
one(adjective, past, then, previously)
4
previous(adjective, last, late, old)
4
some time ago(expression, idiom, late, earlier)
4
then
3
ages ago(expression, adjective, late, old)
3
in times past(expression, adjective, idiom, past)
3
simultaneously
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APASmart Define. (2016). once thesaurus. Retrieved September 26, 2026, from https://smartdefine.org/once/thesaurus/synonyms
ChicagoSmart Define. 2016. "once thesaurus" https://smartdefine.org/once/thesaurus/synonyms (accessed September 26, 2026).
HarvardSmart Define 2016, once thesaurus, Smart Define, viewed 26 September, 2026, <https://smartdefine.org/once/thesaurus/synonyms>.
MLASmart Define. "once thesaurus" 30 March 2016. Web. 26 September 2026. <https://smartdefine.org/once/thesaurus/synonyms>