unionisation vs British spelling

unionisation and British spelling both are nouns.

Word	Noun	Adjective	Verb	Adverb
unionisation	Yes	No	No	No
British spelling	Yes	No	No	No

unionisation (noun)	British spelling (noun)
act of forming labor unions	English orthography used in the UK, Ireland and most of the Commonwealth (characterized by 'analyse', 'centre' and 'useable')