Source : Webster's Revised Unabridged Dictionary (1913)

Practitioner \Prac*ti"tion*er\, n. [From {Practician}.]
   1. One who is engaged in the actual use or exercise of any
      art or profession, particularly that of law or medicine.
      --Crabbe.

   2. One who does anything customarily or habitually.

   3. A sly or artful person. --Whitgift.

   {General practitioner}. See under {General}, 2.

Source : WordNet®

practitioner
     n : someone who practices a learned profession [syn: {practician}]