violence vs hostility

violence and hostility both are nouns.

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

As nouns, hostility is a hypernym of violence; that is, hostility is a word with a broader meaning than violence:

Other hypernyms of violence include aggression.

violence (noun)	hostility (noun)
an act of aggression (as one against a person who resists)	violent action that is hostile and usually unprovoked
the property of being wild or turbulent	a hostile (very unfriendly) disposition
a turbulent state resulting in injuries and destruction etc.	the feeling of a hostile person
	a state of deep-seated ill-will