hostility vs aggression

hostility and aggression both are nouns.

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

As nouns, hostility and aggression are synonyms defined as:

hostility and aggression: violent action that is hostile and usually unprovoked

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

hostility (noun)	aggression (noun)
violent action that is hostile and usually unprovoked	violent action that is hostile and usually unprovoked
a hostile (very unfriendly) disposition	deliberately unfriendly behavior
the feeling of a hostile person	the act of initiating hostilities
a state of deep-seated ill-will	a disposition to behave aggressively
	a feeling of hostility that arouses thoughts of attack