2
before now(expression, adverb, earlier, then, before)
2
before this(expression, adverb, earlier, then, before)
2
bypast(adjective, late, old, past, previous)
2
down memory lane(expression, idiom, adverb, dead, late)
2
eons ago(expression, adverb, earlier, then, before)
2
erewhile(adverb, earlier, then, before, once)
2
ex-(adjective, late, old, past, previous)
2
future
2
gone(adjective, dead, past, lost, previous)
2
immemorial(last, original, past, primitive, venerable)
2
in former times(expression, idiom, adverb, earlier, then)
2
in the olden days(expression, idiom, adverb, late, earlier)
2
in the past(verb, expression, idiom, adverb, phrasal verb)
2
lately(adverb, earlier, then, before, once)
2
long ago(expression, idiom, adverb, late, old)
2
of old(expression, adverb, last, original, dead)
2
of yore(expression, adverb, last, original, dead)
2
old-time(adjective, last, original, dead, past)
2
olden days(expression, adverb, late, old, past)
2
oldfangled(adjective, last, original, dead, past)
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APASmart Define. (2015). erstwhile thesaurus. Retrieved September 20, 2026, from https://smartdefine.org/erstwhile/thesaurus/synonyms
ChicagoSmart Define. 2015. "erstwhile thesaurus" https://smartdefine.org/erstwhile/thesaurus/synonyms (accessed September 20, 2026).
HarvardSmart Define 2015, erstwhile thesaurus, Smart Define, viewed 20 September, 2026, <https://smartdefine.org/erstwhile/thesaurus/synonyms>.
MLASmart Define. "erstwhile thesaurus" 14 April 2015. Web. 20 September 2026. <https://smartdefine.org/erstwhile/thesaurus/synonyms>