A lake in Bariloche, Argentina

A lake in the Andes Mountains

A lake in the Lake District, Cumbria, England

A lake (from Latin: lacus) is a large body of water (larger and deeper than a pond) within a body of land. As a lake is separated from the ocean, it is not a sea. Some lakes are very big, and people in the past sometimes called them seas. Lakes do not flow like rivers, but many have rivers flowing into and out of them.