6
half-baked(adjective, dull, simple, slow, silly)
6
imbecile(adjective, dull, simple, silly, foolish)
6
senseless(adjective, dull, simple, slow, silly)
6
thickheaded(adjective, simple, ability, slow, stupid)
5
weak-minded(adjective, dull, simple, slow, stupid)
5
acquiescent(adjective, calm, quiet, humble, shy)
5
answerless(adjective, calm, quiet, humble, shy)
5
boneheaded(adjective, simple, slow, stupid, impulsive)
5
bovine(adjective, dull, heavy, stupid, impassive)
5
breathless(beat, confused, rambling, amazed, astonished)
5
can't say boo to a goose(adjective, calm, quiet, humble, shy)
5
clueless(adjective, stupid)
5
dotty(adjective, foolish)
5
insane(foolish, crazy, impractical, half-baked, doomed)
5
lamblike(adjective, calm, quiet, humble, shy)
5
mindless(adjective, dull, simple, slow, silly)
5
screwy
5
silence(verb, calm, dull, quiet, suppress)
5
still(verb, adjective, adverb, calm, dull)
5
tight-lipped(adjective, close, quiet, soft, low)
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APASmart Define. (2016). dumb thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/dumb/thesaurus/synonyms
ChicagoSmart Define. 2016. "dumb thesaurus" https://smartdefine.org/dumb/thesaurus/synonyms (accessed September 22, 2026).
HarvardSmart Define 2016, dumb thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/dumb/thesaurus/synonyms>.
MLASmart Define. "dumb thesaurus" 29 March 2016. Web. 22 September 2026. <https://smartdefine.org/dumb/thesaurus/synonyms>