11
foolish(adjective, simple, rough, careless, silly)
11
hackneyed(adjective, set, hard, simple, flat)
11
lacklustre
11
lessen(verb, stop, quiet, check, reduce)
11
moderate(verb, adjective, stop, check, reduce)
11
muddy(verb, adjective, reduce, diminish, lower)
11
pedestrian(adjective, set, simple, flat, excite)
11
quiet(verb, adjective, calm, quiet, check)
11
run-of-the-mill(adjective, set, flat, silly, common)
11
slothful(adjective, flat, low, sad, slow)
11
uneventful(adjective, simple, low, plain, ordinary)
11
wearying(adjective, boring, tedious, dreary, irritating)
10
banal(adjective, set, hard, weak, simple)
10
bovine(adjective, careless, stupid, impassive, unresponsive)
10
brainless(adjective, simple, slow, silly, foolish)
10
clouded(adjective, obscure, dark, gloomy, dim)
10
cold(adjective, calm, tough, severe, flat)
10
comatose(adjective, slow, careless, relaxed, heavy)
10
feeble-minded(adjective, simple, ability, slow, offensive)
10
half-witted(adjective, simple, ability, slow, offensive)
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APASmart Define. (2016). dull thesaurus. Retrieved September 23, 2026, from https://smartdefine.org/dull/thesaurus/synonyms
ChicagoSmart Define. 2016. "dull thesaurus" https://smartdefine.org/dull/thesaurus/synonyms (accessed September 23, 2026).
HarvardSmart Define 2016, dull thesaurus, Smart Define, viewed 23 September, 2026, <https://smartdefine.org/dull/thesaurus/synonyms>.
MLASmart Define. "dull thesaurus" 29 March 2016. Web. 23 September 2026. <https://smartdefine.org/dull/thesaurus/synonyms>