2
gruesome(adjective, appearance, terrible, hopeless)
2
hideous(adjective, appearance, terrible, hopeless)
2
homicidal
2
horrid(adjective, appearance, terrible, hopeless)
2
hurtful(adjective, mean, severe, harsh, unpleasant)
2
icy(adjective, hard, tough, severe, cold)
2
illiberal
2
intolerable
2
intransigent(adjective, persistent, constant, pitiless, unyielding)
2
malignant(adjective, mean, cruel, vicious, hateful)
2
offensive(adjective, unpleasant, vicious, wicked, painful)
2
oppressive
2
perverse(adjective, nasty, cruel, wicked, senseless)
2
rancorous(adjective, mean, evil, nasty, harsh)
2
rigorous(adjective, hard, tough, difficult, harsh)
2
shameless(adjective, hard, tough, evil, harsh)
2
sinful(adjective, evil, nasty, harsh, corrupt)
2
steely(adjective, cold, cruel, unfeeling, unsympathetic)
2
strict(adjective, hard, rough, harsh, cruel)
2
terrible(adjective, appearance, hard, severe, rough)
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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>