specialise vs specialiser

specialise is not a noun while specialiser is a noun.

Word	Noun	Adjective	Verb	Adverb
specialise	No	No	Yes	No
specialiser	Yes	No	No	No

specialise (noun)	specialiser (noun)
	an expert who is devoted to one occupation or branch of learning

specialise (verb)	specialiser (verb)
become more focused on an area of activity or field of study
suit to a special purpose
evolve so as to lead to a new species or develop in a way most suited to the environment
be specific about
devote oneself to a special area of work