vomit up vs sick

vomit up is not a noun while sick is a noun.

Word	Noun	Adjective	Verb	Adverb
vomit up	No	No	Yes	No
sick	Yes	Yes	Yes	No

As verbs, vomit up and sick are synonyms defined as:

Other synonyms of vomit up include barf, be sick, cast, cat, chuck, disgorge, honk, puke, purge, regorge, regurgitate, retch, spew, spue, throw up, upchuck, vomit.

vomit up (noun)	sick (noun)
	people who are sick

vomit up (adjective)	sick (adjective)
	affected by an impairment of normal physical or mental function
	shockingly repellent; inspiring horror
	having a strong distaste from surfeit
	affected with madness or insanity
	deeply affected by a strong feeling
	(of light) lacking in intensity or brightness; dim or feeble
	feeling nausea; feeling about to vomit

vomit up (verb)	sick (verb)
eject the contents of the stomach through the mouth	eject the contents of the stomach through the mouth