ptosis vs prolapsus

ptosis and prolapsus both are nouns.

Word	Noun	Adjective	Verb	Adverb
ptosis	Yes	No	No	No
prolapsus	Yes	No	No	No

As nouns, prolapsus is a hypernym of ptosis; that is, prolapsus is a word with a broader meaning than ptosis:

ptosis: drooping of the upper eyelid caused by muscle paralysis and weakness
prolapsus: the slipping or falling out of place of an organ (as the uterus)

Other hypernyms of ptosis include descensus, prolapse.

ptosis (noun)	prolapsus (noun)
drooping of the upper eyelid caused by muscle paralysis and weakness	the slipping or falling out of place of an organ (as the uterus)