overspecialise vs Australian spelling

overspecialise is not a noun while Australian spelling is a noun.

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

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

overspecialise (verb)	Australian spelling (verb)
become overly specialized