A river of central Asia, which rises in the Altai Mountains in northern China and flows westwards into north-eastern Kazakhstan, where it turns north-west into Russia, joining the River Ob near its mouth. Its length is 4,248 km (2,655 miles).
Definition of Irtysh in US English:
Irtysh
proper nounər-
A river in central Asia that rises in the Altai Mountains in northern China and flows west into northeastern Kazakhstan, where it turns northwest to join the Ob River near its mouth in Russia. Its length is 2,655 miles (4,248 km).