rancor vs hostility

rancor and hostility both are nouns.

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

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

Other hypernyms of rancor include enmity, ill will.

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