commence vs commencement

commence is not a noun while commencement is a noun.

Word	Noun	Adjective	Verb	Adverb
commence	No	No	Yes	No
commencement	Yes	No	No	No

commence (noun)	commencement (noun)
	the act of starting something
	an academic exercise in which diplomas are conferred
	the time at which something is supposed to begin

commence (verb)	commencement (verb)
take the first step or steps in carrying out an action
set in motion, cause to start
get off the ground