heiress vs inheritor

heiress and inheritor both are nouns.

Word	Noun	Adjective	Verb	Adverb
heiress	Yes	No	No	No
inheritor	Yes	No	No	No

As nouns, inheritor is a hypernym of heiress; that is, inheritor is a word with a broader meaning than heiress:

heiress: a female heir
inheritor: a person who is entitled by law or by the terms of a will to inherit the estate of another

Other hypernyms of heiress include heir, heritor, adult female, woman.

heiress (noun)	inheritor (noun)
a female heir	a person who is entitled by law or by the terms of a will to inherit the estate of another