Old magistrate (5)
I believe the answer is:
reeve
'old magistrate' is the definition.
(historical type of magistrate or judge)
This is all the clue.
(Other definitions for reeve that I've seen before include "Old English magistrate or bailiff" , "[PILGRIM in the CANTERBURY TALES]" , "Comic actor" , "Former official - female ruff" , "Historical magistrate" .)