Definition of "Specialize" :

verb: evolve so as to lead to a new species or develop in a way most suited to the environment

verb: become more focused on an area of activity or field of study

"She specializes in Near Eastern history."

verb: suit to a special purpose

"Specialize one's research."

verb: be specific about

verb: devote oneself to a special area of work

"She specializes in honey bees."