12
direct(adjective, complete, smooth, right, energetic)
12
regular(adjective, calm, quiet, smooth, right)
12
savorless(adjective, dull, weak, nasty, offensive)
12
supine(adjective, smooth, level, down, lying)
12
unbroken(adjective, calm, quiet, direct, smooth)
12
weak(adjective, dull, hard, smooth, gentle)
11
banal(adjective, dull, set, hard, weak)
11
arid(adjective, dull, excite, stupid, ordinary)
11
blah(adjective, calm, dull, quiet, weak)
11
digs(noun, place, base, house, home)
11
fixed(adjective, change, strong, definite, manner)
11
flavorless(adjective, dull, weak, taste, excite)
11
flavourless(adjective, characteristic)
11
mat(noun, adjective, dull, light, level)
11
prone(adjective, smooth, level, down, lying)
11
two-dimensional
11
unequivocal(adjective, complete, plain, energetic, big)
11
uniform(adjective, calm, dull, quiet, smooth)
11
watery(adjective, dull, hard, weak, plain)
11
wishy-washy(adjective, dull, weak, plain, mild)
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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>