The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.
a flooded depression of the earth’s surface, the bottom of which lies at least partly below sea level while the water surface lies above (for example, Lake Baikal or Lake Ladoga).
The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.