procreate vs brood

procreate is not a noun while brood is a noun.

Word	Noun	Adjective	Verb	Adverb
procreate	No	No	Yes	No
brood	Yes	No	Yes	No

As verbs, brood is a hyponym of procreate; that is, brood is a word with a more specific, narrower meaning than procreate:

procreate: have offspring or produce more individuals of a given animal or plant
brood: sit on (eggs)

Other hyponyms of procreate include propagate, fructify, set, breed, multiply, cover, hatch, incubate.

procreate (noun)	brood (noun)
	the young of an animal cared for at one time

procreate (verb)	brood (verb)
have offspring or produce more individuals of a given animal or plant	sit on (eggs)
	think moodily or anxiously about something
	be in a huff; be silent or sullen
	be in a huff and display one's displeasure
	hang over, as of something threatening, dark, or menacing