gynaecology vs Australian spelling

gynaecology and Australian spelling both are nouns.

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

gynaecology (noun)	Australian spelling (noun)
the branch of medicine that deals with the diseases and hygiene of women	English orthography used in Australia (characterized by 'analyse', 'centre', 'usable')