weir

[weer] /wɪər/

noun

a small dam in a river or stream.

a fence, as of brush or narrow boards, or a net set in a stream, channel, etc., for catching fish.

Origin

before 900; Middle English were, Old English wer, derivative of root of werian to defend, dam up

Examples from the web for weir

To blame the weir for environmental destruction which has already occurred is political humbug.
Spawning fish were transferred upstream of the weir, while sea lampreys were destroyed.
Enhanced oil spill recovery rate using the weir skimmer.
weir sticks are commercially calibrated stick or staff gage type devices which may be placed by hand upon the crest of a weir.
weir spacing is dependent on the streamflow leaving the weir and its intersection with the downstream structure or bank.
The weir is some way upstream of the lock, at the northern end of ray mill island.

British Dictionary definitions for weir

weir

/wɪə/

noun

a low dam that is built across a river to raise the water level, divert the water, or control its flow

a series of traps or enclosures placed in a stream to catch fish

Word Origin

Old English wer; related to Old Norse ver, Old Frisian were, German Wehr

Weir

/wɪə/

noun

Judith. born 1954, Scottish composer: her operas include A Night at the Chinese Opera (1987), and Armida (2005)

Peter. born 1944, Australian film director; his films include Dead Poets Society (1989), The Truman Show (1998), and Master and Commander (2003)

Word Origin and History for weir

Old English wer "dam, fence, enclosure," especially one for catching fish (related to werian "dam up"), from Proto-Germanic *warjanan (cf. Old Norse ver, Old Frisian and Middle Dutch were, Dutch weer, Old High German wari, German Wehr "defense, protection," Gothic warjan "to defend, protect"), from PIE *wer- "to cover, shut" (cf. Sanskrit vatah "enclosure," vrnoti "covers, wraps, shuts;" Lithuanian uzveriu "to shut, to close;" Old Persian *pari-varaka "protective;" Latin (op)erire "to cover;" Old Church Slavonic vora "sealed, closed," vreti "shut;" Old Irish feronn "field," properly "enclosed land").

Encyclopedia Article for weir

any control or barrier placed in an open channel to permit measurement of water discharge. The latter may be computed from a formula expressing the discharge in terms of crest length of the weir, depth of flow above the weir, weir geometry, and other factors. A variety of weirs have been used in streams, the so-called sharp-crested and trapezoidal forms being relatively common; but broad-crested, triangular, and contracted weirs are also favoured in certain circumstances. Spillways, controls, and embankments designed to permit discharge measurements are simply different kinds of broad-crested weirs

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