people of colour vs Australian spelling

people of colour and Australian spelling both are nouns.

Word	Noun	Adjective	Verb	Adverb
people of colour	Yes	No	No	No
Australian spelling	Yes	No	No	No

people of colour (noun)	Australian spelling (noun)
a race with skin pigmentation different from the white race (especially Blacks)	English orthography used in Australia (characterized by 'analyse', 'centre', 'usable')