65 entries under determined topic. ×

17
hard(adjective, tough, severe, firm, attitude)
14
obdurate(adjective, person, hard, tough, severe)
9
inflexible(adjective, person, hard, tough, firm)
8
adamant(adjective, person, feelings, resolute)
8
firm(adjective, set, strong, hard, tough)
8
stubborn(adjective, characteristic, quality, hard, careless)
6
adamantine(adjective, strong, firm, stiff)
6
unrelenting(adjective, hard, tough, harsh)
6
unyielding(adjective, set, hard, tough, firm)
5
hard-nosed(adjective, hard, resolute, unfeeling)
5
intransigent(adjective, fixed, resolute, stubborn)
5
obstinate(adjective, fixed, resolute, stubborn)
5
ossified(adjective, firm, solid, resolute)
5
unbending(adjective, hard, firm, solid, careless)
5
unforgiving(adjective, person, hard, tough, harsh)
3
hardheaded(adjective, resolute, uncompromising, unshakeable)
3
inexorable(adjective, hard, tough, harsh)
3
mulish(adjective, fixed, resolute, stubborn)
3
opinionated(adjective, fixed, resolute, stubborn)
3
relentless(adjective, hard, tough, harsh, cold)
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APASmart Define. (2016). hardened thesaurus. Retrieved September 24, 2026, from https://smartdefine.org/hardened/thesaurus/synonyms
ChicagoSmart Define. 2016. "hardened thesaurus" https://smartdefine.org/hardened/thesaurus/synonyms (accessed September 24, 2026).
HarvardSmart Define 2016, hardened thesaurus, Smart Define, viewed 24 September, 2026, <https://smartdefine.org/hardened/thesaurus/synonyms>.
MLASmart Define. "hardened thesaurus" 29 March 2016. Web. 24 September 2026. <https://smartdefine.org/hardened/thesaurus/synonyms>