causative vs tributary

causative is not a noun while tributary is a noun.

Word	Noun	Adjective	Verb	Adverb
causative	No	Yes	No	No
tributary	Yes	Yes	No	No

causative (noun)	tributary (noun)
	a branch that flows into the main stream

causative (adjective)	tributary (adjective)
producing an effect	tending to bring about; being partly responsible for
	paying tribute
	(of a stream) flowing into a larger stream