A pond is a body of water smaller than a lake. Used for small bodies of water, generally smaller than one would require a boat to cross; Also: garden pond (see water garden), engineered treatment features (see treatment pond), and field units in agriculture (for example, "pondfields" for rice or taro culture) and aquaculture.
The term is also used for temporary accumulation of water from runoff (ponded water).
Due to the closed environment of ponds, such small bodies of water normally developed self contained eco-systems. Ponds in heavily vegetated areas also display the formation of "scum", which is a common term for dead and decaying vegetation condensing on the water skin of the pond.