20
unwavering(adjective, determined, steady, definite, resolute)
17
obstinate(adjective, mean, strong, hard, tough)
17
unbendable(adjective, determined, resolute, obstinate, uncompromising)
15
adamant(adjective, mean, strong, hard, secure)
15
unshakeable(adjective, determined, resolute, uncompromising)
12
steady(adjective, clear, strong, secure, solid)
11
hard-nosed(adjective, mean, hard, secure, determined)
11
unfaltering(adjective, clear, firm, solid, certain)
9
set in stone(expression, adjective, idiom, mean, hard)
9
unswerving
8
persistent(adjective, strong, tough, firm, determined)
8
tenacious(adjective, strong, tough, firm, determined)
7
constant(adjective, firm, certain, steady, definite)
7
dogged(adjective, mean, strong, hard, tough)
7
hanging tough(expression, adjective, mean, hard, determined)
7
pertinacious(adjective, tough, firm, determined, resolute)
7
solid(adjective, strong, hard, secure, tough)
7
stable(adjective, strong, hard, secure, continue)
7
standing pat(adjective, determined, resolute, obstinate, uncompromising)
7
staunch
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APASmart Define. (2015). unshakable thesaurus. Retrieved September 26, 2026, from https://smartdefine.org/unshakable/thesaurus/synonyms
ChicagoSmart Define. 2015. "unshakable thesaurus" https://smartdefine.org/unshakable/thesaurus/synonyms (accessed September 26, 2026).
HarvardSmart Define 2015, unshakable thesaurus, Smart Define, viewed 26 September, 2026, <https://smartdefine.org/unshakable/thesaurus/synonyms>.
MLASmart Define. "unshakable thesaurus" 10 April 2015. Web. 26 September 2026. <https://smartdefine.org/unshakable/thesaurus/synonyms>