flapper vs young woman

flapper and young woman both are nouns.

Word	Noun	Adjective	Verb	Adverb
flapper	Yes	No	No	No
young woman	Yes	No	No	No

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

flapper: a young woman in the 1920s who flaunted her unconventional conduct and dress
young woman: a young female

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

flapper (noun)	young woman (noun)
a young woman in the 1920s who flaunted her unconventional conduct and dress	a young female