What is "akinji"

Akinji or akindji (, literally, "raider", plural: akıncılar, ) were irregular light cavalry, scout divisions (deli) and advance troops of the Ottoman Empire's military. When the pre-existing Turkish ghazis were incorporated into the Ottoman Empire's military they became known as "akıncı." They were one of the first divisions to face the opposing military and were known for their prowess in battle. Unpaid they lived and operated as raiders on the frontiers of the Ottoman Empire, subsisting totally on plunder. There is a distinction made between "akıncı" and " deli" cavalry.