Om (river)The Om is a river in the south of the Western Siberian plains in Russia. It is a right tributary of the Irtysh. It is long, and has a drainage basin of. The name is probably from the word om "quiet" in the language of the Baraba Tatars.CourseThe Om rises in the Vasyugan Swamp at the border of Novosibirsk and Tomsk oblasts. It flows mainly across the Baraba Lowland of the West Siberian Plain. The city of Omsk is situated at the confluence of Om and Irtysh, and Ust-Tarka at the confluence of the Om and the Tarka rivers. The main tributaries are the Icha, Kama and Tartas.