1
brutish(adjective, evil, nasty, harsh, violent)
1
bullhead(adjective, mean, hard, tough, harsh)
1
by the book(expression, adjective, idiom, strong, hard)
1
cast-iron
1
chilly
1
cold-blooded(adjective, mean, hard, evil, nasty)
1
cold fish(expression, adjective, mean, hard, stubborn)
1
coldhearted(adjective, mean, hard, severe, harsh)
1
committed(adjective, resolute)
1
compassionless(adjective, mean, hard, severe, harsh)
1
courageous(adjective, resolute)
1
cutthroat(adjective, mean, hard, severe, harsh)
1
dauntless(adjective, resolute)
1
dead set(adjective, determined, resolute, uncompromising, unshakeable)
1
dead set on(expression, adjective, idiom, harsh, cruel)
1
degenerate(adjective, evil, nasty, harsh, vicious)
1
deliberate(adjective, resolute)
1
demanding
1
demoniac(adjective, evil, nasty, harsh, vicious)
1
depraved(adjective, evil, nasty, harsh, vicious)
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APASmart Define. (2016). implacable thesaurus. Retrieved September 20, 2026, from https://smartdefine.org/implacable/thesaurus/synonyms
ChicagoSmart Define. 2016. "implacable thesaurus" https://smartdefine.org/implacable/thesaurus/synonyms (accessed September 20, 2026).
HarvardSmart Define 2016, implacable thesaurus, Smart Define, viewed 20 September, 2026, <https://smartdefine.org/implacable/thesaurus/synonyms>.
MLASmart Define. "implacable thesaurus" 24 March 2016. Web. 20 September 2026. <https://smartdefine.org/implacable/thesaurus/synonyms>