wier

Noun

weir (countable and uncountable, plural weirs)

1. (countable) An adjustable dam placed across a river to regulate the flow of water downstream.
   • Though Hambleden's parish register records the death, in 1753, of a bargeman 'Kill'd by accident, shooting ye lock', the turbulent waters of Mill End weir on the River Thames, about a mile from the village, still attract canoeists.1980, AA Book of British Villages, Drive Publications Ltd, page 214, photo caption
2. (countable) A fence placed across a river to catch fish.
   • The Taff is naturally a good salmon river, the Ely a sea trout river, but what with weirs and pollusions the fish have been pretty well exterminated.1879, Annual Report of the Inspectors of Salmon Fisheries, page 65
3. (obsolete) Seaweed.

See all 13 meanings of weir