101 entries under heartless topic. ×

10
stern(adjective, person, appearance, mean, hard)
10
tough(adjective, hard, severe, rough, harsh)
9
dog-eat-dog(adjective, mean, hard, harsh, cruel)
9
uncompromising(adjective, hard, rough, harsh, cruel)
8
cold(adjective, mean, hard, tough, severe)
8
stony-hearted(adjective, cold, cruel, unfeeling, unsympathetic)
8
unsparing(adjective, mean, severe, rough, difficult)
7
mortal(adjective, mean, harsh, cruel, determined)
6
feral(adjective, mean, harsh, violent, cruel)
5
adamant(adjective, person, mean, hard, rough)
5
cold-hearted(adjective, hard, tough, severe, cold)
5
compassionless(adjective, mean, hard, cruel, unfeeling)
5
hard-boiled(adjective, person, hard, severe, rough)
5
uncaring(adjective, person, mean, hard, tough)
4
unappeasable(adjective, mean, harsh, cruel, determined)
4
uncalled-for(adjective, mean, cruel, senseless, pitiless)
4
unmoved(adjective, cold, cruel, unfeeling, unsympathetic)
3
apathetic(adjective, person, hard, tough, severe)
3
exacting(adjective, hard, tough, severe, rough)
3
frigid(adjective, hard, rocky, pebbly)
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APASmart Define. (2016). merciless thesaurus. Retrieved September 30, 2026, from https://smartdefine.org/merciless/thesaurus/synonyms
ChicagoSmart Define. 2016. "merciless thesaurus" https://smartdefine.org/merciless/thesaurus/synonyms (accessed September 30, 2026).
HarvardSmart Define 2016, merciless thesaurus, Smart Define, viewed 30 September, 2026, <https://smartdefine.org/merciless/thesaurus/synonyms>.
MLASmart Define. "merciless thesaurus" 31 March 2016. Web. 30 September 2026. <https://smartdefine.org/merciless/thesaurus/synonyms>