commencement vs birth

commencement and birth both are nouns.

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

As nouns, birth is a hyponym of commencement; that is, birth is a word with a more specific, narrower meaning than commencement:

Other hyponyms of commencement include incipience, incipiency, starting point, terminus a quo, threshold.

commencement (noun)	birth (noun)
the act of starting something	the event of being born
an academic exercise in which diplomas are conferred	a baby born; an offspring
the time at which something is supposed to begin	the process of giving birth
	the kinship relation of an offspring to the parents
	the time when something begins (especially life)

commencement (verb)	birth (verb)
	cause to be born