rumble vs emit

rumble is a noun but emit is not a noun.

Word	Noun	Adjective	Verb	Adverb
rumble	Yes	No	Yes	No
emit	No	No	Yes	No

As verbs, emit is a hypernym of rumble; that is, emit is a word with a broader meaning than rumble:

Other hypernyms of rumble include let loose, let out, utter.

rumble (noun)	emit (noun)
a fight between rival gangs of adolescents
a servant's seat (or luggage compartment) in the rear of a carriage
a loud low dull continuous noise

rumble (verb)	emit (verb)
to utter or emit low dull rumbling sounds	expel (gases or odors)
make a low noise	express audibly; utter sounds (not necessarily words)
	give off, send forth, or discharge; as of light, heat, or radiation, vapor, etc.