jeune fille vs young woman

jeune fille and young woman both are nouns.

Word	Noun	Adjective	Verb	Adverb
jeune fille	Yes	No	No	No
young woman	Yes	No	No	No

As nouns, young woman is a hypernym of jeune fille; that is, young woman is a word with a broader meaning than jeune fille:

Other hypernyms of jeune fille include fille, girl, miss, missy, young lady.

jeune fille (noun)	young woman (noun)
a girl or young woman who is unmarried	a young female