2
wild(adjective, violent, cruel, vicious, fierce)
2
without mercy(expression, adjective, vicious, fierce)
1
adamant(adjective, mean, harsh, cruel, vicious)
1
atrocious
1
avaricious(adjective, hard, tough, harsh, cruel)
1
beastly
1
brute
1
calloused
1
closed(adjective, coldhearted)
1
cold of heart(expression, idiom)
1
disagreeable(adjective, coldhearted)
1
extreme
1
fell(adjective, violent, cruel, vicious, fierce)
1
flinthearted
1
forbidding(adjective, hard, tough, harsh, cruel)
1
frightful(adjective, violent, cruel, vicious, fierce)
1
gory
1
gratuitous(adjective, mean, severe, harsh, cruel)
1
grim(adjective, mean, hard, tough, severe)
1
hard-bitten(adjective, hard, tough, harsh, cruel)
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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>