devote oneself to a special area of work
"She specializes in honey bees"
"This baker specializes in French bread"
be specific about
"Could you please specify your criticism of my paper?"
suit to a special purpose
"specialize one's research"
"this kind of beak has become specialized in certain Galapagos finches"
become more focused on an area of activity or field of study
"She specializes in Near Eastern history"
evolve so as to lead to a new species or develop in a way most suited to the environment
"Over millions of years, these small rodents specialised into distinct species that could thrive in every unique corner of the forest."
Non-Oxford British English standard spelling of specialize.
"The new clinic has decided to specialise in treating rare skin conditions rather than handling general cases."