Khwarezmian (Khwarazmian, Khorezmian, Chorasmian) is an extinct East Iranian language closely related to Sogdian. The language was spoken in the area of Khwarezm (Chorasmia), centered in the lower Amu Darya south of the Aral Sea (the northern part of the modern Republic of Uzbekistan, and the adjacent areas of Turkmenistan and Kazakhstan). Knowledge of Khwarezmian is limited to its Middle Iranian stage and, as with Sogdian, little is known of its ancient form. The noted scholar W.B. Henning was preparing a dictionary of Khwarezmian when he died, leaving it unfinished.