British spelling vs water vapour

British spelling and water vapour both are nouns.

Word	Noun	Adjective	Verb	Adverb
British spelling	Yes	No	No	No
water vapour	Yes	No	No	No

British spelling (noun)	water vapour (noun)
English orthography used in the UK, Ireland and most of the Commonwealth (characterized by 'analyse', 'centre' and 'useable')	water in a vaporous form diffused in the atmosphere but below boiling temperature