Sipahi (Ottoman Turkish:سپاهی sipâhi‎, Turkish pronunciation: [sipaːhi]) were two types of Ottoman cavalry corps, including the fief-holding provincial timarli sipahi, which constituted most of the army, and the regular kapikulu sipahi, palace troops. Other types of cavalry which were not regarded sipahi were the irregular akıncı ("raiders"). The sipahi formed their own distinctive social classes, and were notably in rivalry with the Janissaries, the elite corps of the Sultan.