hollo vs emit

hollo is a noun but emit is not a noun.

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

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

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

hollo (noun)	emit (noun)
a very loud utterance (like the sound of an animal)

hollo (verb)	emit (verb)
utter a sudden loud cry	expel (gases or odors)
cry hollo	express audibly; utter sounds (not necessarily words)
encourage somebody by crying hollo	give off, send forth, or discharge; as of light, heat, or radiation, vapor, etc.