190 entries under fixed topic. ×

51
durable(adjective, calm, strong, sound, secure)
50
set(verb, adjective, business, company, characteristic)
49
enduring(adjective, calm, close, strong, sound)
48
permanent(adjective, calm, strong, secure, tough)
48
unalterable(adjective, characteristic, calm, strong, hard)
47
obdurate(adjective, strong, hard, secure, tough)
46
refractory(adjective, hard, strain, rough, harsh)
44
unwavering(adjective, calm, close, strong, secure)
44
invariable(adjective, calm, strong, secure, strain)
41
unshakable(adjective, mean, strong, hard, complete)
40
solid(adjective, calm, good, close, set)
38
perpetual(adjective, strain, determined, familiar, steady)
38
stabile(adjective, calm, strong, secure, strain)
35
relentless(adjective, mean, strong, hard, tough)
32
adamant(adjective, mean, strong, hard, secure)
30
staunch(noun, adjective, calm, good, close)
29
loyal(adjective, good, close, strong, correct)
29
obstinate(adjective, mean, strong, hard, tough)
29
resolved(adjective, set, severe, harsh, certain)
29
tenacious(adjective, clear, strong, sound, free)
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APASmart Define. (2016). firm thesaurus. Retrieved September 23, 2026, from https://smartdefine.org/firm/thesaurus/synonyms
ChicagoSmart Define. 2016. "firm thesaurus" https://smartdefine.org/firm/thesaurus/synonyms (accessed September 23, 2026).
HarvardSmart Define 2016, firm thesaurus, Smart Define, viewed 23 September, 2026, <https://smartdefine.org/firm/thesaurus/synonyms>.
MLASmart Define. "firm thesaurus" 31 March 2016. Web. 23 September 2026. <https://smartdefine.org/firm/thesaurus/synonyms>