wasteweir

from WordNet (r) 3.0 (2006)

wasteweir
    n 1: a channel that carries excess water over or around a dam or
         other obstruction [syn: {spillway}, {spill}, {wasteweir}]

from The Collaborative International Dictionary of English v.0.48

Wasteweir \Waste"weir`\, n.
   An overfall, or weir, for the escape, or overflow, of
   superfluous water from a canal, reservoir, pond, or the like.
   [1913 Webster]

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