Source : Webster's Revised Unabridged Dictionary (1913)

Approver \Ap*prov"er\, n.
   1. One who approves. Formerly, one who made proof or trial.

   2. An informer; an accuser. [Obs.] --Chaucer.

   3. (Eng. Law) One who confesses a crime and accuses another.
      See 1st {Approvement}, 2.

Approver \Ap*prov"er\, n. [See 2d {Approve}, v. t.] (Eng. Law)
   A bailiff or steward; an agent. [Obs.] --Jacobs.

Source : WordNet®

approver
     n : an authority with power to approve