flume
FLOOM
A narrow, steep-walled gorge through which a river flows fast and deep — also an artificial channel built to carry water, particularly in mining and logging. Natural flumes are dramatic: the water compressed into a slot, accelerated, and roaring. The Flume Gorge in New Hampshire and the Royal Gorge in Colorado are natural flumes.
Etymology
Old French flum, from Latin flumen, a river, from fluere, to flow.
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