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spe·cial·ist 'spesh-(ə-)ləst n a medical practitioner whose practice is limited to a particular class of patients (as children) or of diseases (as skin diseases) or of technique (as surgery) esp a physician who is qualified by advanced training and certification by a specialty examining board to so limit his or her practice
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spe·cial·ist (speshґəl-ist) a physician whose practice is limited to a particular branch of medicine or surgery, especially one who, by virtue of advanced training, is certified by a specialty board as being qualified to so limit his practice.Medical dictionary. 2011.