7
dark
7
demoniac(adjective, evil, nasty, harsh, violent)
7
mortal(adjective, mean, severe, harsh, cruel)
7
not good
7
tyrannical(adjective, hard, tough, evil, nasty)
7
vindictive(adjective, mean, hard, tough, severe)
6
apathetic(adjective, hard, tough, severe, cold)
6
dispassionate(adjective, cold, cruel, unfeeling, unsympathetic)
6
dogged(adjective, appearance, strong, harsh, terrible)
6
hard-boiled(adjective, hard, severe, sharp, rough)
6
rough(adjective, hard, severe, harsh, rude)
6
rude(adjective, hard, severe, sharp, nasty)
6
strict(adjective, hard, rough, harsh, cruel)
6
unflinching(adjective, mean, strong, severe, harsh)
6
unsparing(adjective, mean, severe, harsh, cruel)
5
bitter(adjective, hard, severe, evil, sharp)
5
cold-hearted(adjective, hard, tough, severe, cold)
5
cool(adjective, insensitive)
5
hardened(adjective, hard, tough, severe, harsh)
5
inclement(adjective, harsh, unpleasant, cruel, vicious)
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APASmart Define. (2016). ruthless thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/ruthless/thesaurus/synonyms
ChicagoSmart Define. 2016. "ruthless thesaurus" https://smartdefine.org/ruthless/thesaurus/synonyms (accessed September 22, 2026).
HarvardSmart Define 2016, ruthless thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/ruthless/thesaurus/synonyms>.
MLASmart Define. "ruthless thesaurus" 24 March 2016. Web. 22 September 2026. <https://smartdefine.org/ruthless/thesaurus/synonyms>