891 entries under adjective topic. ×

8
fastened(strong, sound, secure, short)
8
flat(change, certain, definite, resolved)
8
hardy(noun, strong, sound, tough)
8
heavy(set, strong, hard, sound)
8
indefatigable(strong, tough, fit, solid)
8
purposeful(strong, tough, determined, serious)
8
rugged(set, strong, hard, sound)
8
specific(clear, certain, definite, sure)
8
strong-minded(certain, determined, significant, resolution)
8
unswayable(determined, resolute, rigid, obstinate)
7
assertive
7
bent(set, intense, certain, deliberate)
7
bound(set, strong, tough, intense)
7
brave(clear, tough, severe, determined)
7
callous(verb, close, set, fix)
7
crisp(dry, brittle)
7
hanging tough(expression, mean, hard, determined)
7
indurate(verb, close, set, fix)
7
intractable(tough, persistent, rigid, inflexible)
7
mulish(mean, strong, hard, tough)
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APASmart Define. (2016). firm thesaurus. Retrieved September 25, 2026, from https://smartdefine.org/firm/thesaurus/synonyms
ChicagoSmart Define. 2016. "firm thesaurus" https://smartdefine.org/firm/thesaurus/synonyms (accessed September 25, 2026).
HarvardSmart Define 2016, firm thesaurus, Smart Define, viewed 25 September, 2026, <https://smartdefine.org/firm/thesaurus/synonyms>.
MLASmart Define. "firm thesaurus" 31 March 2016. Web. 25 September 2026. <https://smartdefine.org/firm/thesaurus/synonyms>