53 entries under simple topic. ×

8
blockheaded(adjective, dull, ability, slow)
8
dimwitted(adjective, dull, slang, ability)
8
witless(adjective, dull, slow, silly)
7
ignorant(adjective, dull, slow, silly)
7
vacuous(adjective, slow, stupid, empty)
6
empty-headed(adjective, silly, foolish, stupid)
6
backward(adjective, dull, slow, silly)
6
daft(adjective, slow, silly, foolish)
6
half-baked(adjective, dull, slow, silly)
6
imbecile(adjective, dull, silly, foolish)
6
senseless(adjective, dull, slow, silly)
6
thickheaded(adjective, ability, slow, stupid)
5
weak-minded(adjective, dull, slow, stupid)
5
boneheaded(adjective, slow, stupid, impulsive)
5
mindless(adjective, dull, slow, silly)
4
simple-minded(adjective, dull, slow, silly)
4
daffy(adjective, slow, silly, foolish)
4
lumpish(adjective, dull, slow, heavy)
4
oafish(adjective, dull, slow, stupid)
3
insensate(adjective, dull, slow, informal)
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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>