stunt woman vs adult female

stunt woman and adult female both are nouns.

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

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

Other hypernyms of stunt woman include double, woman.

stunt woman (noun)	adult female (noun)
a female stand-in for movie stars to perform dangerous stunts	an adult female person (as opposed to a man)