widow vs adult female

widow and adult female both are nouns.

Word	Noun	Adjective	Verb	Adverb
widow	Yes	No	Yes	No
adult female	Yes	No	No	No

As nouns, adult female is a hypernym of widow; that is, adult female is a word with a broader meaning than widow:

Other hypernyms of widow include woman.

widow (noun)	adult female (noun)
a woman whose husband is dead especially one who has not remarried	an adult female person (as opposed to a man)

widow (verb)	adult female (verb)
cause to be without a spouse