immobilisation vs Australian spelling

immobilisation and Australian spelling both are nouns.

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

immobilisation (noun)	Australian spelling (noun)
the act of limiting movement or making incapable of movement	English orthography used in Australia (characterized by 'analyse', 'centre', 'usable')
fixation (as by a plaster cast) of a body part in order to promote proper healing