Dervish
A dervish is someone treading a Sufi Muslim ascetic path or "Tariqah", known for their extreme poverty and austerity, focused on the universal values of love and service, deserting the illusions of ego to reach God. In most Sufi orders, a dervish is known to practice dhikr through physical exertions or religious practices to attain the ecstatic trance to reach Allah.
Whirling dervishes, Rumi Fest 2007
The whirling dance or Sufi whirling that is proverbially associated with dervishes is best known in the West by the practices (performances) of the Mevlevi order in Turkey, and is part of a formal ceremony known as the Sema. It is, however, also practiced by other orders. The Sema is only one of the many Sufi ceremonies performed to try to reach religious ecstasy . The name Mevlevi comes from the Persian poet Rumi, who was a dervish himself. This practice, though not intended as entertainment, has become a tourist attraction in Turkey.
Sama is a means of meditating on God through focusing on melodies and dancing. It brings out a person's love of God, purifies the soul, and is a way of finding God. This practice is said to reveal what is already in one's heart, rather than creating emotions.
http://www.rahgoshaymuseum.com/en/museum-sections/481-dervish-room-en#sigProGalleriaceec2fd636