Iqa'at

Iqa' (Arabic: إيقاع; plural iqa'at, إيقاعات) are rhythmic modes or rhythmic patterns used in Arabic music.[1] The greatest variety of iqa' (ranging from two to 48 beats) are used in the muwashshah of Arabic classical music. There are reputed to be over 100 iqa',[2] but many of them have fallen out of fashion and are rarely if ever used in performance.

In Ottoman classical music, the corresponding term is usul.