pond
Synonym discussion
Sense: noun/1
Pond, pool, lake, and puddle all describe water staying in one place, but they are used in different situations. A pond is a small area of still water outdoors, often large enough for fish, plants, or ducks. A pool is broader: it can mean a natural patch of water, a swimming pool, or even liquid collecting somewhere. A lake is much larger and is usually treated as a major natural feature. A puddle is shallow rainwater on the ground and is often temporary. Fishpond is more specific than pond because it suggests a pond kept for raising or holding fish. Compare: 'The children fed ducks at the pond,' but 'A puddle formed by the bus stop after the storm.'
Etymology
Pond has been used in English since Middle English. It probably developed from an older form related to 'pound', which once meant an enclosed place. That history matches the idea of water being held inside a bounded area rather than flowing away.