Mahdi

n.
  1. Among Mohammedans, the last imam or leader of the faithful. The Sunni, the largest sect of the Mohammedans, believe that he is yet to appear.

The title has been taken by several persons in countries where Mohammedanism prevails, -- notably by Mohammad Ahmed, who overran the Egyptian Sudan, and in 1885 captured Khartum, his soldiers killing General Gordon, an Englishman, who was then the Egyptian governor of the region.