cof·​fer·​dam | \ ˈkȯ-fər-ˌdam How to pronounce cofferdam (audio) , ˈkä- \

Definition of cofferdam

1 : a watertight enclosure from which water is pumped to expose the bottom of a body of water and permit construction (as of a pier)
2 : a watertight structure for making repairs below the waterline of a ship

Examples of cofferdam in a Sentence

Recent Examples on the Web If the plan goes through, all the water from the American side of the falls will temporarily be diverted to Horseshoe Falls in Canada using a cofferdam. Popular Mechanics, "Niagara Falls May Go Dry for the First Time in Nearly 50 Years," 25 Jan. 2016 Activities for all ages range from hands-on exploration of concepts to in-depth mini-classes about building cofferdams, measuring salinity and shipbuilding. Houston Chronicle, "Calendar: What's Pi Day?," 11 Mar. 2018 Mr. Altschuler said a flotation could be built around the vessel and it could be extricated from the mud with a method known as a cofferdam and restored at the site. Corey Kilgannon, New York Times, "A Submarine Is Stuck in the Muck in Hackensack," 12 June 2017 This one took place on Feb. 18, 1986, when the cofferdam built in preparation for the construction of Auburn Dam collapsed above Folsom Lake. David Caraccio,, "Back when a freight train blast shocked the area (and other historic Sacramento events)," 27 Apr. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'cofferdam.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of cofferdam

1736, in the meaning defined at sense 1

History and Etymology for cofferdam

coffer entry 1 + dam entry 1

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The first known use of cofferdam was in 1736

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Cite this Entry

“Cofferdam.” Dictionary, Merriam-Webster, Accessed 15 Apr. 2021.

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