Lake (noun)

1. A large body of water surrounded by land.
2. A large area of water on the earth's surface, not part of the sea.
3. A body of water on a planet or moon.

Origin:

Old english lacu, of germanic origin; related to dutch meer and german see.

Examples:

1. They went to the lake for the weekend.
2. The lake was surrounded by mountains.
3. The lake was frozen over.
4. They fished in the lake.
5. He swam in the lake.