To make someone an alumnus or alumna; to graduate from a school or institution.
From alumnus + -ate (verb suffix). A rare technical term from academic contexts, likely of 20th-century origin.
This is an extremely rare verb—most people just say 'graduate from' rather than 'alumniate'—but it exists in some formal academic documents to mean 'to cause someone to become an alumnus.'
Complete word intelligence in one call. Free tier — 50 lookups/day.