decametre vs Australian spelling

decametre and Australian spelling both are nouns.

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

decametre (noun)	Australian spelling (noun)
a metric unit of length equal to ten meters	English orthography used in Australia (characterized by 'analyse', 'centre', 'usable')