9
immovable(adjective, secure, firm, solid, determined)
9
indefatigable(adjective, strong, firm, determined, steady)
9
invariant(adjective, even, same)
9
monotonous(adjective, dull, regular, boring, fixed)
9
reliable(adjective, calm, good, close, strong)
9
trustworthy(adjective, good, close, strong, sound)
8
indestructible(adjective, tough, stable, sturdy, enduring)
8
level(adjective, calm, quiet, smooth, right)
8
repeated(adjective, dull, steady, stable, regular)
8
repetitive(adjective, continuous, repetitious)
8
solid(verb, adjective, calm, good, strong)
8
stubborn(adjective, secure, firm, determined, steady)
8
tenacious(adjective, strong, tough, flat, firm)
8
tireless(adjective, strong, firm, determined, steady)
7
ardent(adjective, close, kind, correct, keen)
7
connected(adjective, steady, fixed, persistent, continuous)
7
general(adjective, reasonable, common, ordinary, natural)
7
homogeneous(adjective, regular, fixed, persistent, even)
7
immortal(adjective, abundant, unrestrained, endless, everlasting)
7
obstinate(adjective, moderate, firm, determined, serious)
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APASmart Define. (2016). constant thesaurus. Retrieved September 21, 2026, from https://smartdefine.org/constant/thesaurus/synonyms
ChicagoSmart Define. 2016. "constant thesaurus" https://smartdefine.org/constant/thesaurus/synonyms (accessed September 21, 2026).
HarvardSmart Define 2016, constant thesaurus, Smart Define, viewed 21 September, 2026, <https://smartdefine.org/constant/thesaurus/synonyms>.
MLASmart Define. "constant thesaurus" 12 February 2016. Web. 21 September 2026. <https://smartdefine.org/constant/thesaurus/synonyms>