hymen vs mucous membrane

hymen and mucous membrane both are nouns.

Word	Noun	Adjective	Verb	Adverb
hymen	Yes	No	No	No
mucous membrane	Yes	No	No	No

As nouns, mucous membrane is a hypernym of hymen; that is, mucous membrane is a word with a broader meaning than hymen:

hymen: a fold of tissue that partly covers the entrance to the vagina of a virgin
mucous membrane: mucus-secreting membrane lining all body cavities or passages that communicate with the exterior

Other hypernyms of hymen include mucosa.

hymen (noun)	mucous membrane (noun)
a fold of tissue that partly covers the entrance to the vagina of a virgin	mucus-secreting membrane lining all body cavities or passages that communicate with the exterior