white woman vs adult female

white woman and adult female both are nouns.

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

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

Other hypernyms of white woman include Caucasian, White, White person, woman.

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