excretion vs vomit

excretion and vomit both are nouns.

Word	Noun	Adjective	Verb	Adverb
excretion	Yes	No	No	No
vomit	Yes	No	Yes	No

As nouns, vomit is a hyponym of excretion; that is, vomit is a word with a more specific, narrower meaning than excretion:

excretion: waste matter (as urine or sweat but especially feces) discharged from the body
vomit: the matter ejected in vomiting

excretion (noun)	vomit (noun)
the bodily process of discharging waste matter	the reflex act of ejecting the contents of the stomach through the mouth
waste matter (as urine or sweat but especially feces) discharged from the body	a medicine that induces nausea and vomiting
	the matter ejected in vomiting

excretion (verb)	vomit (verb)
	eject the contents of the stomach through the mouth