A Gerefa was a local Headman of Rohan, a subordinate of the local Eorl, Aldorman or Marshall.In Eriador the title was known as Reeve (Westron) or Riff and applied to the servants of the Canótaran, the Shire-Reeves (Q."Tranndur") were the local judges and Lawspeakers, the Hobbitish title Shirrif was derived from it although the Shirrifs of later times were rather preservers or game-keepers than an official police-force.
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