eye colour vs Australian spelling

eye colour and Australian spelling both are nouns.

Word	Noun	Adjective	Verb	Adverb
eye colour	Yes	No	No	No
Australian spelling	Yes	No	No	No

eye colour (noun)	Australian spelling (noun)
The pigmentation of the eye's iris.	English orthography used in Australia (characterized by 'analyse', 'centre', 'usable')