parentage vs adulthood

parentage and adulthood both are nouns.

Word	Noun	Adjective	Verb	Adverb
parentage	Yes	No	No	No
adulthood	Yes	No	No	No

As nouns, adulthood is a hypernym of parentage; that is, adulthood is a word with a broader meaning than parentage:

parentage: the state of being a parent
adulthood: the state (and responsibilities) of a person who has attained maturity

parentage (noun)	adulthood (noun)
the hereditary derivation of an individual	the state (and responsibilities) of a person who has attained maturity
the kinship relation of an offspring to the parents	the period of time in your life after your physical growth has stopped and you are fully developed
the state of being a parent