backwater

[Eng. back (adv.), and water.] 1. Gen. Water in a stream which, meeting with some impediment in its progre , is thrown backward. "Mr. Temple, on reaching the backwater of a river which had been quite shallow in the morning, found it ten feet deep." -Reader , vol. ii., No. 47: Nov.21, 1863. 2. Spec. Water in a mill-race thrown back by the turning of a waterwheel, by the overflow of the river below, or by ice, that it cannot flow forward. When its course is unimpeded it is called in Scotland tailwater .