commencement ceremony vs graduation

commencement ceremony and graduation both are nouns.

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

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

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

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

commencement ceremony (noun)	graduation (noun)
an academic exercise in which diplomas are conferred	the act of arranging in grades
	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