D defs.my
Entry 3 senses Webster, 1913

Weir

/(wēr)/ · IPA /wɪə̯/
01 n. 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.
  1. 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. 2.
    A fence of stakes, brushwood, or the like, set in a stream, tideway, or inlet of the sea, for taking fish.
  3. 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.