98 entries under fierce topic. ×

14
relentless(adjective, animal, mean, hard, tough)
13
inhumane(adjective, animal, person, mean, hard)
13
unforgiving(adjective, person, mean, hard, tough)
12
bloodthirsty(adjective, severe, nasty, harsh, violent)
12
inexorable(adjective, mean, hard, tough, severe)
11
murderous(adjective, hard, tough, harsh, violent)
11
unrelenting(adjective, animal, mean, hard, tough)
10
implacable(adjective, animal, mean, hard, tough)
10
insensitive(adjective, hard, tough, severe, harsh)
10
obdurate(adjective, mean, hard, tough, severe)
8
grim(adjective, animal, mean, hard, tough)
8
inflexible(adjective, severe, harsh, cruel, determined)
7
bestial(adjective, animal, mean, severe, nasty)
7
fell(adjective, animal, mean, harsh, violent)
7
feral(adjective, mean, harsh, violent, cruel)
7
strict(adjective, severe, harsh, cruel, determined)
7
unyielding(adjective, mean, hard, tough, severe)
6
rigid(adjective, severe, harsh, cruel, determined)
6
sadistic(adjective, person, mean, nasty, harsh)
6
uncompromising(adjective, severe, harsh, cruel, determined)
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APASmart Define. (2016). pitiless thesaurus. Retrieved September 23, 2026, from https://smartdefine.org/pitiless/thesaurus/synonyms
ChicagoSmart Define. 2016. "pitiless thesaurus" https://smartdefine.org/pitiless/thesaurus/synonyms (accessed September 23, 2026).
HarvardSmart Define 2016, pitiless thesaurus, Smart Define, viewed 23 September, 2026, <https://smartdefine.org/pitiless/thesaurus/synonyms>.
MLASmart Define. "pitiless thesaurus" 24 March 2016. Web. 23 September 2026. <https://smartdefine.org/pitiless/thesaurus/synonyms>