a former inlet of the North Sea in the N coast of the Netherlands sealed off from the sea by a dam in 1932, dividing it into the Waddenzee and the freshwater IJsselmeer, with several large reclaimed areas
Zuider Zee in American English
(ˈzaɪdər ˈzi; Dutch ˈzɔɪdəʀ ˈzeɪ)
former arm of the North Sea, which extended into the Netherlands: its S section was shut off from the North Sea by dikes