fille vs adult female

fille and adult female both are nouns.

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

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

Other hypernyms of fille include woman.

fille (noun)	adult female (noun)
a young female	an adult female person (as opposed to a man)