British spelling vs bicolour

British spelling is a noun but bicolour is not a noun.

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

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

British spelling (adjective)	bicolour (adjective)
	having two colors