26
unshakable(adjective, mean, strong, hard, complete)
24
insistent(adjective, set, determined, steady, resolute)
24
stationary(adjective, move, calm, quiet, strong)
23
fast(adjective, adverb, strong, complete, secure)
23
unchangeable(adjective, strong, complete, secure, flat)
23
unrelenting(adjective, mean, hard, firm, determined)
22
obstinate(adjective, mean, hard, rough, firm)
22
relentless(adjective, mean, hard, firm, determined)
21
immutable(adjective, hard, secure, rough, firm)
20
constant(adjective, strong, complete, secure, tough)
20
immobile(adjective, move, calm, quiet, strong)
20
unwavering(adjective, strong, secure, flat, firm)
19
adamant(adjective, mean, strong, hard, secure)
19
stable(adjective, adverb, calm, quiet, strong)
18
definite(adjective, set, clear, strong, complete)
18
enduring(adjective, strong, sound, tough, flat)
18
invariable(adjective, severe, harsh, solid, ordinary)
18
rooted(verb, adjective, strong, hard, secure)
18
steady(adjective, adverb, move, strong, sound)
16
certain(noun, adjective, change, clear, complete)
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APASmart Define. (2016). fixed thesaurus. Retrieved September 20, 2026, from https://smartdefine.org/fixed/thesaurus/synonyms
ChicagoSmart Define. 2016. "fixed thesaurus" https://smartdefine.org/fixed/thesaurus/synonyms (accessed September 20, 2026).
HarvardSmart Define 2016, fixed thesaurus, Smart Define, viewed 20 September, 2026, <https://smartdefine.org/fixed/thesaurus/synonyms>.
MLASmart Define. "fixed thesaurus" 16 March 2016. Web. 20 September 2026. <https://smartdefine.org/fixed/thesaurus/synonyms>