7
indifferent(adjective, calm, hard, careless, cold)
7
strict(adjective, strong, hard, tough, severe)
7
thick-skinned(noun, adjective, calm, mean, hard)
7
unsentimental(adjective, hard, sound, tough, reasonable)
6
case-hardened(noun, adjective, hard, careless, indifferent)
6
cold(adjective, calm, hard, tough, harsh)
6
hard-nosed(adjective, mean, strong, hard, tough)
6
insensible(adjective, bad, strong, hard, tough)
6
pragmatic(adjective, hard, sound, simple, tough)
6
rough(adjective, person, strong, hard, simple)
6
ruthless(adjective, hard, severe, sharp, rough)
6
stern(adjective, hard, tough, severe, rough)
6
unresponsive(adjective, calm, person, bad, hard)
5
aloof(adjective, calm, hard, indifferent, restrained)
5
cool(adjective, calm, indifferent, restrained, detached)
5
dispassionate(adjective, calm, sensible, cold, cruel)
5
down-to-earth(adjective, calm, hard, sound, simple)
5
hard-bitten(adjective, hard, tough, rough, harsh)
5
inhuman(adjective, bad, hard, cold, cruel)
5
merciless(adjective, person, hard, severe, rough)
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APASmart Define. (2016). hard-boiled thesaurus. Retrieved September 25, 2026, from https://smartdefine.org/hard-boiled/thesaurus/synonyms
ChicagoSmart Define. 2016. "hard-boiled thesaurus" https://smartdefine.org/hard-boiled/thesaurus/synonyms (accessed September 25, 2026).
HarvardSmart Define 2016, hard-boiled thesaurus, Smart Define, viewed 25 September, 2026, <https://smartdefine.org/hard-boiled/thesaurus/synonyms>.
MLASmart Define. "hard-boiled thesaurus" 23 March 2016. Web. 25 September 2026. <https://smartdefine.org/hard-boiled/thesaurus/synonyms>