British spelling vs theorisation

British spelling and theorisation both are nouns.

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

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