98 entries under merciless topic. ×

3
rigorous(adjective, hard, tough, harsh, intense)
3
spiteful(adjective, mean, evil, nasty, harsh)
3
unforgiving(adjective, mean, hard, tough, severe)
3
unkind(adjective, animal, mean, evil, nasty)
3
unrelenting(adjective, animal, mean, hard, tough)
3
unsympathetic(adjective, animal, mean, severe, harsh)
2
cold(adjective, mean, sharp, harsh, intense)
2
stern(adjective, mean, hard, severe, rough)
2
depraved(adjective, evil, nasty, harsh, violent)
2
dog-eat-dog(adjective, mean, severe, harsh, cruel)
2
implacable(adjective, animal, mean, hard, tough)
2
inexorable(adjective, mean, hard, tough, severe)
2
malicious(adjective, animal, mean, nasty, harsh)
2
monstrous(adjective, great, evil, nasty, harsh)
2
rancorous(adjective, mean, severe, evil, nasty)
2
rigid(adjective, harsh, cruel, determined, persistent)
2
sinful(adjective, evil, nasty, harsh, violent)
2
stringent(adjective, harsh, cruel, determined, persistent)
2
uncompromising(adjective, clear, hard, tough, severe)
2
unstoppable(adjective, harsh, cruel, determined, persistent)
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APASmart Define. (2016). fierce thesaurus. Retrieved September 29, 2026, from https://smartdefine.org/fierce/thesaurus/synonyms
ChicagoSmart Define. 2016. "fierce thesaurus" https://smartdefine.org/fierce/thesaurus/synonyms (accessed September 29, 2026).
HarvardSmart Define 2016, fierce thesaurus, Smart Define, viewed 29 September, 2026, <https://smartdefine.org/fierce/thesaurus/synonyms>.
MLASmart Define. "fierce thesaurus" 28 March 2016. Web. 29 September 2026. <https://smartdefine.org/fierce/thesaurus/synonyms>