brain vs brain cell

brain and brain cell both are nouns.

Word	Noun	Adjective	Verb	Adverb
brain	Yes	No	Yes	No
brain cell	Yes	No	No	No

brain (noun)	brain cell (noun)
that part of the central nervous system that includes all the higher nervous centers; enclosed within the skull; continuous with the spinal cord	a nerve cell in the brain
mental ability
that which is responsible for one's thoughts, feelings, and conscious brain functions; the seat of the faculty of reason
the brain of certain animals used as meat
someone who has exceptional intellectual ability and originality

brain (verb)	brain cell (verb)
hit on the head
kill by smashing someone's skull