spe·cial·ism /ˈspɛʃəˌlɪzəm/
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  Spe·cial·ism n. Devotion to a particular and restricted part or branch of knowledge, art, or science; as, medical specialism.
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  specialism
       n 1: the concentration of your efforts on a particular field of
            study or occupation
       2: the special line of work you have adopted as your career;
          "his specialization is gastroenterology" [syn: specialization,
           specialisation, specialty, speciality]