comatose vs unconscious

comatose is not a noun while unconscious is a noun.

Word	Noun	Adjective	Verb	Adverb
comatose	No	Yes	No	No
unconscious	Yes	Yes	No	No

comatose (noun)	unconscious (noun)
	that part of the mind wherein psychic activity takes place of which the person is unaware

comatose (adjective)	unconscious (adjective)
relating to or associated with a coma	not conscious; lacking awareness and the capacity for sensory perception as if asleep or dead
in a state of deep and usually prolonged unconsciousness; unable to respond to external stimuli	without conscious volition
	(followed by `of') not knowing or perceiving