Australian spelling vs synthesise

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

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

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

Australian spelling (verb)	synthesise (verb)
	combine so as to form a more complex, product