[ir-tish] 
| a river in central Asia, flowing NW from the Altai Mountains in China through NE Kazakhstan and the Russian Federation to the Ob River. ab. 1840 mi. (2960 km) long. |
| Ir·tysh or Ir·tish (ĭr-tĭsh') A river of northwest China, eastern Kazakhstan, and central Russia flowing about 4,264 km (2,650 mi) generally northwest to the Ob River. It is navigable for much of its course. |