spout vs rabbit on

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

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

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

Other synonyms of spout include jabber, mouth off, rant, rave.

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

spout (verb)	rabbit on (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