hostility vs bitterness

hostility and bitterness both are nouns.

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

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

hostility (noun)	bitterness (noun)
violent action that is hostile and usually unprovoked	the property of having a harsh unpleasant taste
a hostile (very unfriendly) disposition	a rough and bitter manner
the feeling of a hostile person	the taste experience when quinine or coffee is taken into the mouth
a state of deep-seated ill-will	a feeling of deep and bitter anger and ill-will