imperforate hymen vs maidenhead

imperforate hymen and maidenhead both are nouns.

Word	Noun	Adjective	Verb	Adverb
imperforate hymen	Yes	No	No	No
maidenhead	Yes	No	No	No

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

imperforate hymen: hymen that is completely closed so that menstrual blood cannot flow out
maidenhead: a fold of tissue that partly covers the entrance to the vagina of a virgin

Other hypernyms of imperforate hymen include hymen, virginal membrane.

imperforate hymen (noun)	maidenhead (noun)
hymen that is completely closed so that menstrual blood cannot flow out	a fold of tissue that partly covers the entrance to the vagina of a virgin