Water turned back in its course by an obstruction, an opposing current, or the flow of the tide, as in a sewer or river channel, or across a river bar.

An accumulation of water overflowing the low lands, caused by an obstruction.

Water thrown back by the turning of a waterwheel, or by the paddle wheels of a steamer.

(4): Water surface of stream raised above its normal level by a natural or artificial obstruction.

A still body of water or a still portion of a larger body of water, unaffected by the flow of the larger body of water. An example would be a small stagnant branch of a river.

a body of water that was created by a flood or tide or by being held or forced back by a dam; "the bayous and backwaters are breeding grounds for mosquitos"

The increase in water surface elevation relative to the elevation occurring under natural channel and floodplain conditions. It is induced by a bridge or other structure that obstructs or constricts the otherwise unobstructed flow of water in a channel.

A body of stagnant water connected to a river.

Part of a river where water has minimal velocity and silting occurs

an area of a lake or river, which is off the main body of water. Backwaters are generally shallow and difficult to get in to.

The profile of the water surface upstream when its surface slope is generally less than the bed slope. The backwater curve generally occurs upstream of an obstruction or confluence.

A small, generally shallow body of water attached to the main channel, with little or no current of its own.

Water backed up or retarded in its course as compared with its normal or natural condition of flow. In stream gaging, a rise in stage produced by a temporary obstruction such as ice or weeds, or by the flooding of the stream below. The difference between the observed stage and that indicated by the stage-discharge relation, is reported as backwater.

A flood upstream caused by obstructions downstream, such as ice jams or debris.

The rise in a stream's water surface elevation caused by an obstruction or constriction to the flow, such as by a dam, bridge, culvert, or a temporary obstruction.

The rise in water surface elevation caused by some obstruction such as a narrow bridge opening, buildings or fill material that limits the area through which the water shall flow.

Water returned from the pulp or paper or board making process for re-use.

An unnaturally high stage in stream caused by obstruction or confinement of flow, as by a dam, a bridge, or a levee.  Its measure is the excess of unnatural over natural stage, not the difference in stage upstream and downstream from its cause.

Accumulation of water resulting from an obstruction, limited downstream channel capacity, high tide, or high stages in a connecting stream.