emit vs smoke

emit is not a noun while smoke is a noun.

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

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

emit: give off, send forth, or discharge; as of light, heat, or radiation, vapor, etc.
smoke: emit a cloud of fine particles

Other hyponyms of emit include effuse, reflect, shine, spark, sparkle, radiate, scintillate, fume, reek, shoot, ray, steam.

emit (noun)	smoke (noun)
	the act of smoking tobacco or other substances
	(baseball) a pitch thrown with maximum velocity
	tobacco leaves that have been made into a cylinder
	street names for marijuana
	something with no concrete substance
	an indication of some hidden activity
	a cloud of fine particles suspended in a gas
	a hot vapor containing fine particles of carbon being produced by combustion

emit (verb)	smoke (verb)
expel (gases or odors)	inhale and exhale smoke from cigarettes, cigars, pipes
express audibly; utter sounds (not necessarily words)	emit a cloud of fine particles
give off, send forth, or discharge; as of light, heat, or radiation, vapor, etc.