a river in central Asia, rising in China in the Altai Mountains and flowing west through Kazakhstan, then northwest into Russia to join the Ob River as its chief tributary. Length: 4444 km (2760 miles)
Irtysh in American English
(ɪrˈtɪʃ)
river in central Asia, flowing from NW China northwestward into the Ob: c. 1,850 mi (2,977 km)