hostility vs resentment

hostility and resentment both are nouns.

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

As nouns, resentment is a hyponym of hostility; that is, resentment is a word with a more specific, narrower meaning than hostility:

hostility (noun)	resentment (noun)
violent action that is hostile and usually unprovoked	a feeling of deep and bitter anger and ill-will
a hostile (very unfriendly) disposition
the feeling of a hostile person
a state of deep-seated ill-will