graduation vs commencement ceremony

graduation and commencement ceremony both are nouns.

Word	Noun	Adjective	Verb	Adverb
graduation	Yes	No	No	No
commencement ceremony	Yes	No	No	No

As nouns, graduation and commencement ceremony are synonyms defined as:

graduation and commencement ceremony: an academic exercise in which diplomas are conferred

Other synonyms of graduation include commencement, commencement exercise, graduation exercise.

graduation (noun)	commencement ceremony (noun)
the act of arranging in grades	an academic exercise in which diplomas are conferred
the successful completion of a program of study
a line (as on a vessel or ruler) that marks a measurement
an academic exercise in which diplomas are conferred