(also ushur; Arabic, one-tenth), a religious tax in Muslim countries; usually payable in kind, but sometimes in cash. The ushr was levied annually on people engaged in agriculture, livestock raising, fishing, and crafts.

The tax varied in form and name through different periods of time. It was known as the ikta, dimos, onda, ondalik, and salariye in the Ottoman Empire; as the dah-yak in Iran; and by other names elsewhere. The tax-farming system used in the Middle Ages and to some extent in modern times to collect the ushr frequently resulted in the collection of more than ten percent of the peasants’ income, and sometimes as much as fifty percent.

As the concept of income tax spread, the tax was almost universally abolished; for example, it was eliminated in Algeria in 1918, in Turkey in 1925, and in Tunisia in 1935. It still survives, however, in certain Muslim countries, including Saudi Arabia and the Yemen Arab Republic.