cais·​son | \ ˈkā-ˌsän How to pronounce caisson (audio) , -sᵊn, British also kə-ˈsün\

Definition of caisson

1a : a chest to hold ammunition
b : a usually 2-wheeled vehicle for artillery ammunition attachable to a horse-drawn limber also : a limber with its attached caisson
2a : a watertight chamber used in construction work under water or as a foundation
b : a hollow floating box or a boat used as a floodgate for a dock or basin

Illustration of caisson

Illustration of caisson

caisson 1b

Examples of caisson in a Sentence

Recent Examples on the Web

As was one of the first soldiers to arrive, his job was to deploy concrete caissons that would form a temporary harbor to help soldiers rapidly load cargo onto the beach. Adam Beam, The Seattle Times, "100-year-old WWII veteran awarded French Legion of Honor," 19 Nov. 2018 Construction began in June 2007 and by the following year, a circular hole 76-feet deep and 110 feet across had been dug, surrounded by caissons to support what was supposed to be the skyscraper’s concrete core. Bill Ruthhart,, "Exclusive: Two soaring towers planned for long-languishing Chicago Spire site along Lake Shore Drive," 11 May 2018 Items range from medals, buttons, insignia and signet rings to 18th- and 19th-century cannons and caissons and more than 100 military flags. Meg Jones, Milwaukee Journal Sentinel, "Wisconsin's attic is moving — Wisconsin Historical Society and Wisconsin Veterans Museum move collections," 20 Apr. 2018 Caro: So the caisson is pulled up to the front of White House. Bob Schieffer, CBS News, "The assassination of JFK: As it happened," 26 Oct. 2017 Andy Herrmann, past president of the American Society of Civil Engineers, says the great majority of Texas bridges aren’t vulnerable to damage from heavy rains because they’re built on piles or caissons — often hollow pipe filled with concrete. Sharon Cohen, The Seattle Times, "Harvey began with raging winds, but its legacy will be water," 4 Sep. 2017 As of May, there were 2,019 oil platforms, including caissons and well protectors, in federal waters off Louisiana's coast, according to numbers McDonough presented to the commission. Todd Masson,, "Wildlife & Fisheries proposes more artificial-reef sites for defunct oil platforms," 9 June 2017 The float, sponsored by Regence BlueCross BlueShield of Oregon, features a 40-foot-long faux log mounted on a caisson with 12-foot-high wheels. Special To The Oregonian,, "Grand Floral Parade will have a new route for 2017," 24 May 2017 Mark De Alencar’s wife and five children followed him one last time: six figures, dressed in black, walking behind the caisson that carried his casket through Arlington National Cemetery. James Hohmann, Washington Post, "The Daily 202: Why is Paul Ryan really defending Trump firing Comey?," 11 May 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'caisson.' 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 caisson

circa 1702, in the meaning defined at sense 1a

History and Etymology for caisson

French, from Middle French, from Old Occitan, from caissa chest, from Latin capsa — more at case

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Time Traveler for caisson

The first known use of caisson was circa 1702

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Rhyming Dictionary: Words that rhyme with caisson

Spanish Central: Translation of caisson

Nglish: Translation of caisson for Spanish Speakers Encyclopedia article about caisson

Comments on caisson

What made you want to look up caisson? Please tell us where you read or heard it (including the quote, if possible).


to make a temporary encampment

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