colorful vs monochrome

colorful is not a noun while monochrome is a noun.

Word	Noun	Adjective	Verb	Adverb
colorful	No	Yes	No	No
monochrome	Yes	Yes	No	No

colorful (noun)	monochrome (noun)
	a black-and-white photograph or slide
	painting done in a range of tones of a single color

colorful (adjective)	monochrome (adjective)
having much or varied color	having or appearing to have only one color
having color or a certain color; sometimes used in combination
striking in variety and interest