specialize


specialize (http://definr.com/specialize)

     v 1: become more special; "We specialize in dried flowers" [syn:
          specialise, narrow, narrow down] [ant: diversify,
           diversify]
     2: be specific about [syn: specify, particularize] [ant: generalize]
     3: suit to a special purpose; "specialize one's research" [syn:
         specialise]
     4: devote oneself to a special area of work; "She specializes
        in honey bees"; "This plumber specialized in jacuzzis"