colouring vs colourful

colouring is a noun but colourful is not a noun.

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

colouring (noun)	colourful (noun)
the act or process of changing the color of something
a visual attribute of things that results from the light they emit or transmit or reflect
a digestible substance used to give color to food

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