3
imperceptive(adjective, indifferent, unkind, unresponsive, heartless)
3
impercipient
3
imperturbable(adjective, calm, cool, cold, cruel)
3
implacable(adjective, mean, hard, severe, evil)
3
indurated(adjective, hard, cool, firm, cruel)
3
inure(verb, dull, develop, rough, adjust)
3
irresponsive(adjective, bad, cold, aloof, no feelings)
3
lackadaisical(adjective, indifferent, unsympathetic, inattentive, uninterested)
3
lukewarm(adjective, calm, mean, hard, cool)
3
marble-hearted(adjective, bad, cold, aloof, no feelings)
3
mouthy(adjective, insolent)
3
narcotic(adjective, senseless)
3
phlegmatic(adjective, cool, indifferent, detached, unfriendly)
3
presumptuous(adjective, insolent)
3
rocky(adjective, set, strong, hard, firm)
3
sacrilegious(adjective, insolent)
3
sadistic(adjective, mean, evil, nasty, harsh)
3
sarcastic(adjective, hard, unkind, insolent, cutting)
3
saucy(adjective, insolent)
3
set(verb, adjective, close, fix, hard)
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APASmart Define. (2016). callous thesaurus. Retrieved September 23, 2026, from https://smartdefine.org/callous/thesaurus/synonyms
ChicagoSmart Define. 2016. "callous thesaurus" https://smartdefine.org/callous/thesaurus/synonyms (accessed September 23, 2026).
HarvardSmart Define 2016, callous thesaurus, Smart Define, viewed 23 September, 2026, <https://smartdefine.org/callous/thesaurus/synonyms>.
MLASmart Define. "callous thesaurus" 24 March 2016. Web. 23 September 2026. <https://smartdefine.org/callous/thesaurus/synonyms>