Weir
Weir (wēr) , noun
[Old English wer, Anglo-Saxon wer; akin to German wehr, Anglo-Saxon werian to defend, protect, hinder, German wehren, Gothic warjan; and perhaps to English wary; or compare Sanskrit vr to check, hinder. r142. Compare Garret.]
1.
A dam in a river to stop and raise the water, for the purpose of conducting it to a mill, forming a fish pond, or the like.
2.
A fence of stakes, brushwood, or the like, set in a stream, tideway, or inlet of the sea, for taking fish.
3.
A long notch with a horizontal edge, as in the top of a vertical plate or plank, through which water flows, -- used in measuring the quantity of flowing water.
Also: Wear