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Billabong

Billabong, term used to describe several kinds of bodies of water, all of which are standing, often stagnant, and related to river channels. There are three main types of billabongs: two are caused by the distinctive climate of the Australian interior, which features hot, dry weather interrupted by occasional flooding; a third type is found in rivers in all parts of the world. The word billabong is derived from an Australian Aboriginal word meaning dead river.

In one of the two Australian billabongs, flooding of a river or stream may cause a temporary channel to branch off from, but not lead back to, the main stream. If the temporary channel is deep enough, water will remain there after the flood. The other Australian billabong involves an intermittent river that flows only after heavy rains. When the channel dries, it may leave standing pools, or billabongs, in its deeper parts.

The third type of billabong is found in numerous rivers with a regular flow. A sharp bend in the river's course, called a meander, is eventually cut off by a new channel that forms across the neck of land created by the meander. When this process is complete, the original meander is separated from the river, and its water stops flowing. This feature is also known as an oxbow lake.