16
soporific(noun, adjective, quiet, dry, boring)
16
uninspired(adjective, set, flat, silly, common)
15
cloudy(adjective, obscure, dark, gloomy, miserable)
15
faint(verb, adjective, quiet, reduce, light)
15
fatuous(adjective, silly, foolish, stupid, crazy)
15
ho-hum(adjective, simple, flat, plain, ordinary)
15
indistinct(adjective, quiet, weak, soft, gentle)
15
mundane(adjective, boring, simple, ordinary, tedious)
15
plain(adjective, weak, simple, tough, flat)
15
sad(adjective, unhappy, dark, black, gloom)
15
soften(verb, action, quiet, check, reduce)
15
spiritless(adjective, quiet, weak, kind, soft)
15
stale(adjective, set, hard, weak, simple)
14
benumb(verb, action, quiet, diminish, impair)
14
colorless(adjective, beat, light, weak, simple)
14
damp(verb, adjective, upset, trouble, quiet)
14
indifferent(adjective, calm, quiet, mean, flat)
14
insensitive(noun, adjective, quiet, rough, low)
14
lethargic(adjective, calm, flat, slow, careless)
14
phlegmatic(adjective, calm, tough, slow, relaxed)
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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>