dervish
    n 1: an ascetic Muslim monk; a member of an order noted for
         devotional exercises involving bodily movements

Dervish \Der"vish\, Dervise \Der"vise\, Dervis \Der"vis\, n.
   [Per. derw[=e]sch, fr. OPer. derew to beg, ask alms: cf. F.
   derviche.]
   1. A Turkish or Persian monk, especially one who professes
      extreme poverty and leads an austere life.
      [1913 Webster]

   2. One of the fanatical followers of the Mahdi, in the Sudan,
      in the 1880's.
      [Webster 1913 Suppl.]

   3. in modern times, a member of an ascetic Mohammedan sect
      notable for its devotional exercises, which include
      energetic chanting or shouting and rhythmic bodily
      movement, such as whirling, leading to a trance-like state
      or ecstasy. From these exercises the phrase whirling
      dervish is derived.
      [PJC]

   4. figuratively, a person who whirls or engages in frenzied
      activity reminiscent of the dervish[3] dancing.
      [PJC]