hee-haw vs emit

hee-haw is a noun but emit is not a noun.

Word	Noun	Adjective	Verb	Adverb
hee-haw	Yes	No	Yes	No
emit	No	No	Yes	No

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

Other hypernyms of hee-haw include let loose, let out, utter.

hee-haw (noun)	emit (noun)
a loud laugh that sounds like a horse neighing

hee-haw (verb)	emit (verb)
braying characteristic of donkeys	expel (gases or odors)
	express audibly; utter sounds (not necessarily words)
	give off, send forth, or discharge; as of light, heat, or radiation, vapor, etc.