weir

Everyday

A low wall or dam built across a river to control the flow of water or raise its level; water pours over the top. tree →

In the lessons

In geography lessons about rivers a weir is a human-made feature that controls water, helps mills and measures flow. Fish ladders help salmon get past weirs. Safety lessons warn that the water below a weir can trap swimmers and boats in a dangerous swirling current, so never swim near one. Phrases: over the weir, a weir pool.

Examples

• The river rushes over the weir after heavy rain. tree →
• Salmon leap up the fish ladder beside the weir. tree →
• Never swim near a weir; the current can pull you under. tree →
• The old mill used water from the weir. tree →
• We watched the ducks above the weir. tree →
• The canoeists carried their boats around the weir. tree →

Note

Countable: a weir, weirs. Pronounced like "we're" or "wear" in some accents (UK: WEER). Homophone trap: weir (dam) vs we're (we are); not to be confused with "weird". Safety: weirs look calm but are among the most dangerous places on a river.