5
unoriginal(adjective, dull, set, flat, silly)
4
antique
4
extinct
4
moth-eaten(adjective, dull, flat, silly, commonplace)
4
musty(adjective, dull, flat, silly, commonplace)
4
obsolescent
4
out-dated
4
out-of-date
4
threadbare(adjective, dull, flat, commonplace, stale)
4
unfashionable(adjective, plain, dead, out, square)
3
antediluvian
3
bromidic(adjective, dull, set, flat, silly)
3
conventional(adjective, characteristic, common, stupid, ordinary)
3
cut-and-dried(adjective, fixed, settled, finished, decided)
3
date
3
everyday(adjective, characteristic, dull, plain, common)
3
familiar(adjective, set, common, ordinary, usual)
3
ordinary(adjective, characteristic, dull, set, flat)
3
outdated(adjective, plain, square, old, stale)
3
set(dull, flat, silly, ordinary, commonplace)
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APASmart Define. (2015). old hat thesaurus. Retrieved September 23, 2026, from https://smartdefine.org/old_hat/thesaurus/synonyms
ChicagoSmart Define. 2015. "old hat thesaurus" https://smartdefine.org/old_hat/thesaurus/synonyms (accessed September 23, 2026).
HarvardSmart Define 2015, old hat thesaurus, Smart Define, viewed 23 September, 2026, <https://smartdefine.org/old_hat/thesaurus/synonyms>.
MLASmart Define. "old hat thesaurus" 10 April 2015. Web. 23 September 2026. <https://smartdefine.org/old_hat/thesaurus/synonyms>