colourful vs vividness

colourful is not a noun while vividness is a noun.

Word	Noun	Adjective	Verb	Adverb
colourful	No	Yes	No	No
vividness	Yes	No	No	No

colourful (noun)	vividness (noun)
	chromatic purity: freedom from dilution with white and hence vivid in hue
	interest and variety and intensity

colourful (adjective)	vividness (adjective)
having much or varied color
striking in variety and interest
having color or a certain color; sometimes used in combination