intercessor

noun5

1. •
   One who intercedes.
2. •
   A mediator, one who reconciles enemies or pleads for another.
3. •
   An intermediary, a middleman.

   • Kings were revered, in many cases not merely as priests, that is, as intercessors between man and god, but as themselves gods... — 1894
4. •
   A saint believed to plead for a sinner to God.
5. •
   A bishop who acts during a vacancy in a see.