decolourise vs British spelling

decolourise is not a noun while British spelling is a noun.

Word	Noun	Adjective	Verb	Adverb
decolourise	No	No	Yes	No
British spelling	Yes	No	No	No

decolourise (noun)	British spelling (noun)
	English orthography used in the UK, Ireland and most of the Commonwealth (characterized by 'analyse', 'centre' and 'useable')

decolourise (verb)	British spelling (verb)
cause to become white or lighter in color