Definition of caisson in English:

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Pronunciation: /ˈkeɪs(ə)n/
Pronunciation: /kəˈsuːn/


1A large watertight chamber, open at the bottom, from which the water is kept out by air pressure and in which construction work may be carried out under water.
Example sentences
  • The seal course at the bottom of the caissons is 8 m thick and required about 6,000 m³ of underwater concrete.
  • Rebar cages for the caissons were assembled remotely, moved on-site, and lowered into the hole at night; the hole was filled with concrete, leaving a cold joint at the top of the apron.
  • These were noticed first among men in new industrial applications: tunnelling below water and working in caissons.
1.1A floating vessel or watertight structure used as a gate across the entrance of a dry dock or basin.
Example sentences
  • These floats transported the great floating concrete caissons which formed the sea walls of the Mulberry Harbours.
  • He sailed to the raid in HMS Campbeltown and landed by jumping over the ship's bow onto the caisson to conduct demolition work ashore.
  • The port consisted of a series of caissons forming the outside wall, with various pontoons and jetties inside, mainly following the design of a bailey bridge (big meccano).
2 historical A chest or wagon for holding or conveying ammunition.
Example sentences
  • Graves were everywhere; dead soldiers and horses lay unburied; and destroyed wagons and caissons littered the area.
  • It was impossible to resist the line of World War I toys - including doughboys with fixed bayonets and artillery attached to caissons that were pulled by teams of horses.
  • It has also been speculated that the use of the color purple was adopted because of the use of purple heart wood from Brazil to make caissons for the artillery.


Late 17th century: from French, literally 'large chest', from Italian cassone, the spelling having been altered in French by association with caisse 'case'.

Words that rhyme with caisson

basin, chasten, diapason, hasten, Jason, mason

For editors and proofreaders

Line breaks: cais|son

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