The Collaborative International Dictionary of English v.0.48:

Provisor \Pro*vi"sor\, n. [L., fr. providere: cf. F. proviseur.
   See Provide.]
   1. One who provides; a purveyor. [Obs.] "The chief provisor
      of our horse." --Ford.
      [1913 Webster]

   2. (R. C. Ch.)
      (a) The purveyor, steward, or treasurer of a religious
          house. --Cowell.
      (b) One who is regularly inducted into a benefice. See
          Provision, 5. --P. Plowman.
          [1913 Webster]

   3. (Eng. Hist.) One who procures or receives a papal
      provision. See Provision, 6.
      [1913 Webster]