Origin: 1250–1300; ME
fiers < AF
fers, OF
fiers (nom.) < L
ferus wild, fierce;
cf. feral 1 , ferocious 
Related forms: fiercely, adverb
fierceness, noun
Synonyms:
1. untamed; cruel, fell, brutal; barbarous, bloodthirsty, murderous. Fierce, ferocious, truculent suggest vehemence and violence of temper, manner, or action: fierce in repelling a foe. Ferocious implies fierceness or cruelty, esp. of a bloodthirsty kind, in disposition or action: a ferocious glare; ferocious brutality toward helpless refugees. Truculent suggests an intimidating or bullying fierceness of manner or conduct: His truculent attitude kept them terrified and submissive. 2, 3. furious, passionate, turbulent.
Antonyms:
1. tame, mild.
[feers] 