British spelling vs achromatic colour

British spelling and achromatic colour both are nouns.

Word	Noun	Adjective	Verb	Adverb
British spelling	Yes	No	No	No
achromatic colour	Yes	No	No	No

British spelling (noun)	achromatic colour (noun)
English orthography used in the UK, Ireland and most of the Commonwealth (characterized by 'analyse', 'centre' and 'useable')	a color lacking hue; white or grey or black