1
hatchet job(expression, adjective, mean, severe, harsh)
1
having a killer instinct(expression, adjective, idiom, mean, severe)
1
hostile(adjective, coldhearted)
1
impenitent(adjective, hard, tough, harsh, cruel)
1
indifferent
1
inflexible
1
inhospitable(adjective, coldhearted)
1
intolerant(adjective, hard, tough, harsh, cruel)
1
intransigent
1
iron-fisted(adjective, mean, severe, harsh, cruel)
1
ironfisted(adjective, mean, harsh, cruel, vicious)
1
killer(adjective, mean, harsh, cruel, vicious)
1
lupine(adjective, violent, cruel, vicious, fierce)
1
malevolent(adjective, mean, harsh, cruel, vicious)
1
malign(adjective, coldhearted)
1
mean machine(expression, adjective, mean, severe, harsh)
1
nasty
1
predatory(adjective, violent, cruel, vicious, fierce)
1
rapacious(adjective, violent, cruel, vicious, fierce)
1
ravening(adjective, violent, cruel, vicious, fierce)
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APASmart Define. (2016). unmerciful thesaurus. Retrieved September 25, 2026, from https://smartdefine.org/unmerciful/thesaurus/synonyms
ChicagoSmart Define. 2016. "unmerciful thesaurus" https://smartdefine.org/unmerciful/thesaurus/synonyms (accessed September 25, 2026).
HarvardSmart Define 2016, unmerciful thesaurus, Smart Define, viewed 25 September, 2026, <https://smartdefine.org/unmerciful/thesaurus/synonyms>.
MLASmart Define. "unmerciful thesaurus" 31 March 2016. Web. 25 September 2026. <https://smartdefine.org/unmerciful/thesaurus/synonyms>