The Deima (Russian Дейма, Deime German, Lithuanian Deimena ) is a 37 km long river in the Russian exclave of Kaliningrad. It branches from the Pregel in Gwardeisk ( Tapiau ) from flows from there to Polessk ( Labiau ) and flows into the Curonian Lagoon. The river's name goes back to the Indo-European root * dei, meaning " continuous flow forward".
Shortly before the opening into the lagoon branches in Polessk from the Polesski channel ( Big Friedrichsgraben ), which connects the Deime with the Nemonin ( Nemonien ). This is about the Primorsky channel ( Seckenburger channel ) with the Matrossowka ( Gilgestrom ), a left arm of the Memel, connected.