Source : Webster's Revised Unabridged Dictionary (1913)

Probator \Pro*ba"tor\, n. [L.]
   1. An examiner; an approver. --Maydman.

   2. (O. Eng. Law) One who, when indicted for crime, confessed
      it, and accused others, his accomplices, in order to
      obtain pardon; a state's evidence.