A mill (for whatever purpose) powered by water(noun)
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Use "watermill" in a sentence
"I guess moving your thermos elsewhere to the hills, and making a dam with a watermill is a cheaper approach."
"James Pyman has been commissioned to wrap the site's 18th-century watermill in a lifesize drawing of the mill as it stands today; in the gardens Heather and Ivan Morison have built The Black Cloud, half-sculpture and half-shelter; and in the main gallery a show by Irish artist Eva Rothschild to 9 Oct should remind us that there is tactile, evocative life yet in modernist sculpture."
"Chouettes lived in the attic of our renovated watermill in La France profonde."