synthesise vs British spelling

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

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

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

synthesise (verb)	British spelling (verb)
combine so as to form a more complex, product