9
unsavory(adjective, dull, weak, taste, nasty)
8
certain(adjective, change, total, energetic, definite)
8
continuous(adjective, calm, quiet, direct, smooth)
8
crib(noun, place, base, house, home)
8
definite(adjective, strong, complete, total, energetic)
8
depressed(adjective, dull, quiet, smooth, low)
8
flatly(adverb, strong)
8
foul
8
lodging(noun, place, set, group, base)
8
true(adjective, strong, direct, smooth, right)
8
uninspired(adjective, dull, set, weak, excite)
8
unvarying(adjective, dull, quiet, smooth, right)
7
abode(noun, place, house, home, box)
7
apathetic(adjective, calm, dull, quiet, tough)
7
complete(adjective, total, big, limited, utter)
7
crash pad(noun, expression, place, base, house)
7
inert(adjective, dull, quiet, slow, cold)
7
lacklustre
7
matt
7
matter-of-fact(adjective, calm, dull, cool, simple)
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APASmart Define. (2016). flat thesaurus. Retrieved September 20, 2026, from https://smartdefine.org/flat/thesaurus/synonyms
ChicagoSmart Define. 2016. "flat thesaurus" https://smartdefine.org/flat/thesaurus/synonyms (accessed September 20, 2026).
HarvardSmart Define 2016, flat thesaurus, Smart Define, viewed 20 September, 2026, <https://smartdefine.org/flat/thesaurus/synonyms>.
MLASmart Define. "flat thesaurus" 1 March 2016. Web. 20 September 2026. <https://smartdefine.org/flat/thesaurus/synonyms>