ferocity vs vehemence

ferocity and vehemence both are nouns.

Word	Noun	Adjective	Verb	Adverb
ferocity	Yes	No	No	No
vehemence	Yes	No	No	No

As nouns, ferocity and vehemence are synonyms defined as:

Other synonyms of ferocity include fierceness, furiousness, fury, violence, wildness.

ferocity (noun)	vehemence (noun)
the property of being wild or turbulent	the property of being wild or turbulent
	intensity or forcefulness of expression