enrollment vs ingress

enrollment and ingress both are nouns.

Word	Noun	Adjective	Verb	Adverb
enrollment	Yes	No	No	No
ingress	Yes	No	No	No

As nouns, ingress is a hypernym of enrollment; that is, ingress is a word with a broader meaning than enrollment:

Other hypernyms of enrollment include entering, entrance, entry, incoming.

enrollment (noun)	ingress (noun)
the act of enrolling	the act of entering
the body of people (such as students) who register or enroll at the same time	(astronomy) the disappearance of a celestial body prior to an eclipse