extemporisation vs Australian spelling

extemporisation and Australian spelling both are nouns.

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

extemporisation (noun)	Australian spelling (noun)
a performance given extempore without planning or preparation	English orthography used in Australia (characterized by 'analyse', 'centre', 'usable')