Australian spelling vs sombre

Australian spelling is a noun but sombre is not a noun.

Word	Noun	Adjective	Verb	Adverb
Australian spelling	Yes	No	No	No
sombre	No	Yes	No	No

Australian spelling (noun)	sombre (noun)
English orthography used in Australia (characterized by 'analyse', 'centre', 'usable')

Australian spelling (adjective)	sombre (adjective)
	lacking brightness or color; dull
	grave or even gloomy in character