incapacity vs incapability

incapacity and incapability both are nouns.

Word	Noun	Adjective	Verb	Adverb
incapacity	Yes	No	No	No
incapability	Yes	No	No	No

As nouns, incapability is a hypernym of incapacity; that is, incapability is a word with a broader meaning than incapacity:

incapacity: lack of physical or natural qualifications
incapability: the quality of not being capable -- physically or intellectually or legally

Other hypernyms of incapacity include incapableness.

incapacity (noun)	incapability (noun)
lack of physical or natural qualifications	the quality of not being capable -- physically or intellectually or legally
lack of intellectual power	lack of potential for development