miaou vs emit

miaou is a noun but emit is not a noun.

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

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

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

miaou (noun)	emit (noun)
the sound made by a cat (or any sound resembling this)

miaou (verb)	emit (verb)
make a cat-like sound	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.