Black woman vs adult female

Black woman and adult female both are nouns.

Word	Noun	Adjective	Verb	Adverb
Black woman	Yes	No	No	No
adult female	Yes	No	No	No

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

Other hypernyms of Black woman include African-American, Black, Negro, Negroid, woman, Black person, blackamoor.

Black woman (noun)	adult female (noun)
a woman who is Black	an adult female person (as opposed to a man)