theorisation vs British spelling

theorisation and British spelling both are nouns.

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

theorisation (noun)	British spelling (noun)
the production or use of theories	English orthography used in the UK, Ireland and most of the Commonwealth (characterized by 'analyse', 'centre' and 'useable')