externalise vs British spelling

externalise is not a noun while British spelling is a noun.

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

externalise (noun)	British spelling (noun)
	English orthography used in the UK, Ireland and most of the Commonwealth (characterized by 'analyse', 'centre' and 'useable')

externalise (verb)	British spelling (verb)
make external or objective, or give reality to
regard as objective