The Collaborative International Dictionary of English v.0.48:

Commissary \Com"mis*sa*ry\, n.; pl. Commissaries. [LL.
   commissarius, fr. L. commissus, p. p. of committere to
   commit, intrust to. See Commit.]
   1. One to whom is committed some charge, duty, or office, by
      a superior power; a commissioner.
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            Great Destiny, the Commissary of God. --Donne.
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   2. (Eccl.) An officer of the bishop, who exercises
      ecclesiastical jurisdiction in parts of the diocese at a
      distance from the residence of the bishop. --Ayliffe.
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   3. (Mil.)
      (a) An officer having charge of a special service; as, the
          commissary of musters.
      (b) An officer whose business is to provide food for a
          body of troops or a military post; -- officially
          called commissary of subsistence. [U. S.]
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                Washington wrote to the President of Congress .
                . . urging the appointment of a commissary
                general, a quartermaster general, a commissary
                of musters, and a commissary of artillery. --W.
                                                  Irving
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   Commissary general, an officer in charge of some special
      department of army service; as:
      (a) The officer in charge of the commissariat and
          transport department, or of the ordnance store
          department. [Eng.]
      (b) The commissary general of subsistence. [U. S.]

   Commissary general of subsistence (Mil. U. S.), the head of
      the subsistence department, who has charge of the purchase
      and issue of provisions for the army.
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