12
relentless(adjective, animal, mean, hard, tough)
12
sharp(adjective, mean, strong, great, severe)
12
untamed(adjective, simple, severe, violent, wild)
11
acute(adjective, strong, great, severe, sharp)
11
bestial(adjective, animal, mean, kind, evil)
11
homicidal(adjective, characteristic, cruel, vicious, grim)
11
pitiless(adjective, animal, mean, hard, tough)
11
strong(adjective, strong, severe, difficult, intense)
10
ardent(adjective, strong, keen, nasty, difficult)
10
cutthroat(adjective, mean, severe, harsh, violent)
10
impetuous(adjective, strong, severe, difficult, intense)
10
tumultuous(adjective, violent, confused)
9
extreme(adjective, strong, great, sharp, harsh)
9
frantic(adjective, harsh, intense, passionate, violent)
9
rough(adjective, hard, simple, harsh, violent)
9
terrible(adjective, strong, hard, great, severe)
9
uncontrollable(adjective, hard, severe, rough, harsh)
9
wicked(noun, adjective, mean, clear, bad)
8
awful(adjective, great, tough, violent, terrible)
8
dangerous(adjective, tough, difficult, violent, wicked)
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APASmart Define. (2016). fierce thesaurus. Retrieved September 21, 2026, from https://smartdefine.org/fierce/thesaurus/synonyms
ChicagoSmart Define. 2016. "fierce thesaurus" https://smartdefine.org/fierce/thesaurus/synonyms (accessed September 21, 2026).
HarvardSmart Define 2016, fierce thesaurus, Smart Define, viewed 21 September, 2026, <https://smartdefine.org/fierce/thesaurus/synonyms>.
MLASmart Define. "fierce thesaurus" 28 March 2016. Web. 21 September 2026. <https://smartdefine.org/fierce/thesaurus/synonyms>