introitus vs orifice

introitus and orifice both are nouns.

Word	Noun	Adjective	Verb	Adverb
introitus	Yes	No	No	No
orifice	Yes	No	No	No

As nouns, orifice is a hypernym of introitus; that is, orifice is a word with a broader meaning than introitus:

introitus: entrance or opening to a hollow organ or tube (especially the vaginal opening)
orifice: an aperture or hole that opens into a bodily cavity

Other hypernyms of introitus include opening, porta.

introitus (noun)	orifice (noun)
entrance or opening to a hollow organ or tube (especially the vaginal opening)	an aperture or hole that opens into a bodily cavity