a river in the Lithuanian SSR, a right tributary of the Nemunas (Neman). It is 210 km long and drains an area of 6,140 sq km. It flows through the Central Lithuanian Lowland.
The Nevėžis is fed mainly by snow. High water occurs from February to April; during the rest of the year there may be freshets. The mean flow rate 58 km from the mouth is 18.4 cu m per sec. The river freezes over between November and January; it thaws in February or the first half of April. The cities of Panėvežys and Kėdainiai are situated along the river.