water vapour vs Australian spelling

water vapour and Australian spelling both are nouns.

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

water vapour (noun)	Australian spelling (noun)
water in a vaporous form diffused in the atmosphere but below boiling temperature	English orthography used in Australia (characterized by 'analyse', 'centre', 'usable')