a barrier to obstruct the flow of water, especially one of earth, masonry, etc., built across a stream or river.
a body of water confined by a dam.
any barrier resembling a dam.
a barrier of concrete, earth, etc, built across a river to create a body of water for a hydroelectric power station, domestic water supply, etc
a reservoir of water created by such a barrier
something that resembles or functions as a dam
1275–1325; Middle English < Middle Dutch, Middle Low German, dam; akin to Old English for-demman to stop up, block
1250–1300; Middle English; variant of dame
A barrier built to block the flow of water is called a dam. If you walk along a stream, you can see where beavers have built a dam out of mud and logs. As a verb, dam means to obstruct or blockade as with a dam. If the kids you're babysitting dam up the bathtub drain when you're not paying attention, the water might overflow and cause a waterfall into the living room downstairs. But water isn't the only thing that can be dammed. You shouldn't dam up your emotions — go ahead and scream if you need to.
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It’s made up of 916 turbines that can produce up to 3.65 gigawatts of electricity, making it potentially more powerful than the Hoover Dam.
From Los Angeles Times • Jun. 18, 2026
That water helps replenish San Carlos Reservoir, which was created by the Coolidge Dam.
From Science Daily • Jun. 18, 2026
The Hardah Dam volcanic crater is one of the country's most famous natural landmarks.
From BBC • Jun. 15, 2026
A sales program could target Thunderbox, Carosue Dam, Jundee and/or Kalgoorlie Operations, it says.
From The Wall Street Journal • Jun. 9, 2026
Then there was the time he fixed a broken sluice gate on the Hoover Dam and saved the lives of thousands of people who would have drowned if the dam had burst.
From "The Glass Castle" by Jeannette Walls
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
