furiousness vs ferocity

furiousness and ferocity both are nouns.

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

As nouns, furiousness and ferocity are synonyms defined as:

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

furiousness (noun)	ferocity (noun)
the property of being wild or turbulent	the property of being wild or turbulent