5
dark
5
demoniac(adjective, evil, nasty, harsh, violent)
5
fell(adjective, harsh, violent, cruel, vicious)
5
flinty(adjective, evil, nasty, harsh, vicious)
5
hard-boiled(adjective, person, hard, severe, rough)
5
hellish(adjective, evil, nasty, harsh, violent)
5
intractable(adjective, appearance, hard, severe, rough)
5
rude(adjective, rough, violent, cruel, vicious)
5
stiff(adjective, hard, rough, harsh, cruel)
5
uncaring(adjective, person, mean, hard, tough)
5
unresponsive(adjective, person, feelings, emotions, rocky)
5
villainous(adjective, behavior, wicked, aroused negative, aroused awful feeling)
4
barbarian(adjective, crude, savage)
4
beastly
4
chilly(adjective, person, feelings, emotions, rocky)
4
coldhearted(adjective, mean, hard, severe, harsh)
4
malign(adjective, cruel, vicious, brutal, cold-blooded)
4
nasty(adjective, mean, evil, cruel, negative)
4
rigid(adjective, harsh, cruel, determined, fierce)
4
sanguinary(adjective, hard, tough, harsh, violent)
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APASmart Define. (2016). merciless thesaurus. Retrieved September 28, 2026, from https://smartdefine.org/merciless/thesaurus/synonyms
ChicagoSmart Define. 2016. "merciless thesaurus" https://smartdefine.org/merciless/thesaurus/synonyms (accessed September 28, 2026).
HarvardSmart Define 2016, merciless thesaurus, Smart Define, viewed 28 September, 2026, <https://smartdefine.org/merciless/thesaurus/synonyms>.
MLASmart Define. "merciless thesaurus" 31 March 2016. Web. 28 September 2026. <https://smartdefine.org/merciless/thesaurus/synonyms>