fierceness vs violence

fierceness and violence both are nouns.

Word	Noun	Adjective	Verb	Adverb
fierceness	Yes	No	No	No
violence	Yes	No	No	No

As nouns, fierceness and violence are synonyms defined as:

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

fierceness (noun)	violence (noun)
the property of being wild or turbulent	an act of aggression (as one against a person who resists)
	the property of being wild or turbulent
	a turbulent state resulting in injuries and destruction etc.