mental vs intellectual

mental is not a noun while intellectual is a noun.

Word	Noun	Adjective	Verb	Adverb
mental	No	Yes	No	No
intellectual	Yes	Yes	No	No

mental (noun)	intellectual (noun)
	a person who uses the mind creatively

mental (adjective)	intellectual (adjective)
involving the mind or an intellectual process	appealing to or using the intellect
of or relating to the mind	involving intelligence rather than emotions or instinct
of or relating to the chin- or liplike structure in insects and certain mollusks	of or associated with or requiring the use of the mind
of or relating to the chin or median part of the lower jaw
affected by a disorder of the mind