weir
Pluralweirs
- 1A low dam across a river that controls how much water flows downstream; some have adjustable sections.
Like the lip of a bathtub that keeps the water at one level by letting the excess spill over.
Engineers installed a weir upstream to maintain a steady flow during the dry season.
The old stone weir still controls the water level along that stretch of the canal.
Note
The engineering sense, and the one the word's history explains best: Old English wer comes from werian, "to dam up," from a root meaning "to cover." A weir regulates water rather than stopping it. Water still pours over it, turbulent enough to draw canoeists at Mill End weir on the Thames. It can carry a walkway for clearing trapped debris and working its sluices, or a built-in fishway so migrating fish can pass.
- 2A fence or enclosure placed across a river to trap and catch fish.
Like a funnel that guides fish into a basket they can't escape.
The villagers maintained a weir at the river mouth to harvest migrating fish each fall.
An old wooden weir still spans the creek where his grandfather once trapped eels.
Note
Here the barrier works for the fisherman rather than the water engineer, and the Old Norse cognate ver, "station for fishing," shows a related word turned to the same trade. The noun works readily as a modifier, as in a weir catch of mackerel or weir poles driven into the sand. Such traps stood off Cape Cod as well as across rivers. The damming root behind both uses is told under the river-control meaning.
- 3Seaweed; marine plant growth found along the shore and in the sea.
Note
A meaning that has dropped out of use entirely: weir no longer names anything that grows. A reader who meets the word in old writing about the shore should allow for it, letting context decide between plant and barrier. A writer today should say seaweed and keep weir for the river dam and the fish trap.
Practice
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Origin
From Middle English were, from Old English wer, from werian ("to dam up"), from Proto-West Germanic *warjan and Proto-Germanic *warjaną, ultimately from the Proto-Indo-European root *wer- ("to cover"). It is cognate with Old Norse ver ("station for fishing") and Sanskrit वृणोति (vṛṇóti), and is related to warranty.