rabbit on vs spout

rabbit on is not a noun while spout is a noun.

Word	Noun	Adjective	Verb	Adverb
rabbit on	No	No	Yes	No
spout	Yes	No	Yes	No

As verbs, rabbit on and spout are synonyms defined as:

Other synonyms of rabbit on include jabber, mouth off, rant, rave.

rabbit on (noun)	spout (noun)
	an opening that allows the passage of liquids or grain

rabbit on (verb)	spout (verb)
talk in a noisy, excited, or declamatory manner	talk in a noisy, excited, or declamatory manner
	gush forth in a sudden stream or jet