sick vs laid up

sick is a noun but laid up is not a noun.

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

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

sick (adjective)	laid up (adjective)
affected by an impairment of normal physical or mental function	ill and usually confined
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

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