The definition of ferocious is something very fierce, cruel, extreme or violent.(adjective)
When you are so hungry you could eat a horse, this is an example of a time when you might be described as having a ferocious appetite.
See ferocious in Webster's New World College Dictionary
Origin: < L ferox (gen. ferocis), wild, untamed < ferus, fierce + base akin to oculus, eye + -ous
See ferocious in American Heritage Dictionary 4
Origin: From Latin ferōx, ferōc-, fierce; see ghwer- in Indo-European roots.
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