Definition of "Chagatai"

A male given name of historical usage, most famously borne by the Mongol ruler Chagatai Khan (1183–1242), second son of Genghis Khan and first khan of the Chagatai Khanate, a medieval Mongol and later Turkicized khanate of Central Asia (divided after the 14th century).  examples

An extinct literary Turkic language used in Central Asia and Bashkortostan between the 15th and the 20th century.  examples

(with article, collective) An ethnic group of Uzbekistan.  examples