280 entries under tough topic. ×

5
solidified(adjective, set, firm, solid)
5
wicked(adjective, mean, severe, evil)
4
hard-core(adjective, strong, severe, firm)
4
impenitent(adjective, harsh, careless, indifferent)
4
impervious(adjective, set, firm, solid)
4
indomitable(adjective, set, strong, great)
4
insensate(adjective, severe, careless, indifferent)
4
stiff-necked(adjective, mean, strong, harsh)
4
unremitting(adjective, harsh, cruel, grim)
3
astringent(adjective, strong, severe, sharp)
3
barbarous(adjective, mean, severe, evil)
3
cantankerous(adjective, mean, severe, evil)
3
challenging(adjective, great, difficult, awkward)
3
crusty(adjective, harsh, rude, coarse)
3
forbidding(adjective, person, strong, severe)
3
great(adjective, person, body, strong)
3
hairy(adjective, mean, severe, sharp)
3
hard as nails(expression, adjective, idiom, set, strong)
3
murderous(adjective, harsh, cruel, grim)
3
sour(adjective, severe, evil, sharp)
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APASmart Define. (2016). hard thesaurus. Retrieved September 28, 2026, from https://smartdefine.org/hard/thesaurus/synonyms
ChicagoSmart Define. 2016. "hard thesaurus" https://smartdefine.org/hard/thesaurus/synonyms (accessed September 28, 2026).
HarvardSmart Define 2016, hard thesaurus, Smart Define, viewed 28 September, 2026, <https://smartdefine.org/hard/thesaurus/synonyms>.
MLASmart Define. "hard thesaurus" 24 March 2016. Web. 28 September 2026. <https://smartdefine.org/hard/thesaurus/synonyms>