North American Plains Indian people living mostly in Oklahoma, U.S. Their language is Siouan. The name Osage is a French alliteration of Wazhazhe, the name for one of the two ancient kin groups (Tsishu is the other) from which the tribe descended. They lived variously in the Piedmont and Ozark plateaus and the western Missouri and southeastern Kansas prairies. Their culture was marked by the combination of village agriculture and buffalo hunting. Their villages consisted of longhouses; tepees were used during the hunting season. Their religious ceremonies divided clans into symbolic sky and earth groups. In the late 19th century the Osage were removed to a reservation in Oklahoma. The discovery of oil there made them an unusually prosperous tribe. Early 21st-century population estimates indicated some 16,000 individuals of Osage descent.