Mahdi

Webster's Dictionary

(n.) 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 Nuttall Encyclopedia

E . religious leader), a name given to any Mohammedan fanatic who arises in the interest of the Mohammedan faith, summons the Moslems to war, and leads them to repel the infidel; a kind of Mohammed Messiah armed with the sword for the conquest of the world to the faith.