Source : Webster's Revised Unabridged Dictionary (1913)

Coadjutor \Co`ad*ju"tor\, n. [L. See {Co}-, and {Aid}.]
   1. One who aids another; an assistant; a coworker.

            Craftily outwitting her perjured coadjutor.
                                                  --Sheridan.

   2. (R. C. Ch.) The assistant of a bishop or of a priest
      holding a benefice.

Source : WordNet®

coadjutor
     n : an assistant to a Bishop