demineralisation vs Australian spelling

demineralisation and Australian spelling both are nouns.

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

demineralisation (noun)	Australian spelling (noun)
the removal of minerals and mineral salts from a liquid (especially from water)	English orthography used in Australia (characterized by 'analyse', 'centre', 'usable')
abnormal loss of mineral salts (especially from bone)