10
lazy(adjective, slow, careless, relaxed, indifferent)
10
lumpish(adjective, slow, heavy, sluggish, impassive)
10
mute(verb, adjective, calm, quiet, reduce)
10
shadowy(adjective, weak, soft, gentle, obscure)
10
soft(adjective, quiet, increase, light, weak)
10
still(verb, adjective, calm, quiet, flat)
10
sunless(adjective, dark, gloomy, dim, black)
10
tasteless(adjective, hard, weak, flat, rough)
10
tired(adjective, set, beat, hard, weak)
10
tone down(verb, expression, phrasal verb, quiet, check)
10
unfeeling(noun, adjective, calm, tough, severe)
10
unresponsive(adjective, calm, quiet, flat, slow)
10
weary(adjective, verb, sluggish, upset, reduce)
9
abate(verb, stop, quiet, check, reduce)
9
blank(adjective, quiet, flat, heavy, stupid)
9
cloud(verb, clear, reduce, diminish, lower)
9
deadened(adjective, quiet, weak, boring, tedious)
9
desensitize(verb, quiet, diminish, impair, stifle)
9
fatiguing(adjective, boring, tedious, irritating, exasperating)
9
inanimate(adjective, low, property, still, depressed)
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APASmart Define. (2016). dull thesaurus. Retrieved September 24, 2026, from https://smartdefine.org/dull/thesaurus/synonyms
ChicagoSmart Define. 2016. "dull thesaurus" https://smartdefine.org/dull/thesaurus/synonyms (accessed September 24, 2026).
HarvardSmart Define 2016, dull thesaurus, Smart Define, viewed 24 September, 2026, <https://smartdefine.org/dull/thesaurus/synonyms>.
MLASmart Define. "dull thesaurus" 29 March 2016. Web. 24 September 2026. <https://smartdefine.org/dull/thesaurus/synonyms>