891 entries under adjective topic. ×

36
rock-solid(hard, strain, firmness, compact)
35
relentless(mean, strong, hard, tough)
34
unrelenting(mean, strong, hard, tough)
32
adamant(mean, strong, hard, secure)
31
tough(calm, mean, clear, strong)
30
staunch(noun, calm, good, close)
29
loyal(good, close, strong, correct)
29
obstinate(mean, strong, hard, tough)
29
resolved(set, severe, harsh, certain)
29
tenacious(clear, strong, sound, free)
28
sturdy(calm, strong, hard, sound)
26
unfaltering(strong, complete, total, solid)
24
secure(verb, calm, fix, strong)
24
unflinching(strong, certain, determined, steady)
23
unswerving(close, strong, tough, correct)
22
sure(calm, good, close, clear)
21
decided(set, clear, intense, certain)
21
dogged(mean, strong, hard, tough)
21
established(definite, strong, state, calm)
20
unbendable(determined, unreasonable, resolute, rigid)
10 years ago|51k views|share |citing 
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>