Bailiff
The word was first used in England for the king's officers, such as sheriffs and mayors. It was also  the title for the chief officer of a hundred. The sheriff looked after an area called his bailiwick. Bailiff is kept as a title by the chief magistrates of various towns and the keepers of royal castles, such as the High Bailiff of Westminster, and the Bailiff of Dover Castle. In a medieval manor, a bailiff was in charge of the farming.