metastasise vs British spelling

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

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

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

metastasise (verb)	British spelling (verb)
spread throughout the body