107 entries under tough topic. ×

7
unemotional(adjective, hard, cool, severe)
7
unsympathetic(adjective, hard, severe, careless)
6
apathetic(adjective, person, hard, cool)
6
impenitent(adjective, hard, harsh, careless)
6
impervious(noun, adjective, set, hard)
6
seasoned(adjective, set, strong, hard)
6
unrelenting(adjective, hard, harsh, determined)
6
unyielding(adjective, set, hard, firm)
5
congealed(verb, adjective, set, hard)
5
uncontrite(adjective, hard, harsh, cruel)
5
unforgiving(adjective, person, hard, harsh)
4
jelled(verb, adjective, hard, firm)
4
ruthless(adjective, hard, severe, harsh)
3
cold-hearted(adjective, hard, severe, attitude)
3
inexorable(adjective, hard, harsh, determined)
3
merciless(adjective, person, hard, severe)
3
relentless(adjective, hard, harsh, cold)
3
solid(adjective, set, strong, hard)
2
anesthetized(adjective, hard, severe, cruel)
2
compressed(verb, adjective, set, strong, hard)
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APASmart Define. (2016). hardened thesaurus. Retrieved September 29, 2026, from https://smartdefine.org/hardened/thesaurus/synonyms
ChicagoSmart Define. 2016. "hardened thesaurus" https://smartdefine.org/hardened/thesaurus/synonyms (accessed September 29, 2026).
HarvardSmart Define 2016, hardened thesaurus, Smart Define, viewed 29 September, 2026, <https://smartdefine.org/hardened/thesaurus/synonyms>.
MLASmart Define. "hardened thesaurus" 29 March 2016. Web. 29 September 2026. <https://smartdefine.org/hardened/thesaurus/synonyms>