51 entries under fierce topic. ×

6
inhuman(adjective, mean, hard, tough, harsh)
6
vicious(adjective, mean, harsh, violent, cruel)
5
barbaric(adjective, violent, cruel, vicious)
5
insensitive(adjective, hard, tough, harsh, cruel)
5
severe(adjective, mean, harsh, cruel, vicious)
2
feral(adjective, mean, harsh, violent, cruel)
2
murderous(adjective, hard, tough, harsh, violent)
2
tigerish(adjective, violent, cruel, vicious)
2
violent(adjective, cruel, vicious, savage)
2
wild(adjective, violent, cruel, vicious)
2
without mercy(expression, adjective, vicious)
1
fell(adjective, violent, cruel, vicious)
1
frightful(adjective, violent, cruel, vicious)
1
grim(adjective, mean, hard, tough, severe)
1
lupine(adjective, violent, cruel, vicious)
1
predatory(adjective, violent, cruel, vicious)
1
rapacious(adjective, violent, cruel, vicious)
1
ravening(adjective, violent, cruel, vicious)
1
ravenous(adjective, violent, cruel, vicious)
1
sanguinary(adjective, hard, tough, harsh, violent)
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APASmart Define. (2016). unmerciful thesaurus. Retrieved September 27, 2026, from https://smartdefine.org/unmerciful/thesaurus/synonyms
ChicagoSmart Define. 2016. "unmerciful thesaurus" https://smartdefine.org/unmerciful/thesaurus/synonyms (accessed September 27, 2026).
HarvardSmart Define 2016, unmerciful thesaurus, Smart Define, viewed 27 September, 2026, <https://smartdefine.org/unmerciful/thesaurus/synonyms>.
MLASmart Define. "unmerciful thesaurus" 31 March 2016. Web. 27 September 2026. <https://smartdefine.org/unmerciful/thesaurus/synonyms>