caisson

noun

cais·​son ˈkā-ˌsän How to pronounce caisson (audio)
-sᵊn
British also kə-ˈsün
Synonyms of caissonnext
1
a
: 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
2
a
: 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
3
: coffer sense 3

Illustration of caisson

Illustration of caisson
  • caisson 1b

Examples of caisson in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Ronald Reagan, a noted enthusiast did, and that’s the last time the caisson unit took part. — Tom Vanden Brook, USA TODAY, 6 Jan. 2025 In isolation, against a white background that is actually overcast sky, a hook or a caisson or a sheaf of rebar appears sculptural, abstract, exquisite. — Nick Paumgarten, New Yorker, 23 Feb. 2026 Included in the sale are ADA-compliant plans for an 848-square-foot accessory dwelling unit, with caissons already in place with street access from above. — Sandra Barrera, Oc Register, 13 May 2026 Hitchcock recalled a day during the summer of 2007 when the cannon, now on its caisson and a moveable platform, was tested on the event level of Nationwide Arena, just beyond the ice-resurfacer entrance. — Aaron Portzline, New York Times, 2 Feb. 2026 See All Example Sentences for caisson

Word History

Etymology

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

First Known Use

circa 1702, in the meaning defined at sense 1a

Time Traveler
The first known use of caisson was circa 1702

Phrases Containing caisson

Rhymes for caisson

See All Rhymes for caisson

Browse Nearby Words

Cairo
caisson
caisson crib
See all Nearby Words

Cite this Entry

“Caisson.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/caisson. Accessed 9 Jul. 2026.

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Kids Definition

caisson

noun
cais·​son ˈkā-ˌsän How to pronounce caisson (audio)
ˈkā-sᵊn
1
a
: a chest for ammunition
b
: a usually two-wheeled vehicle for artillery ammunition
2
: a watertight chamber used in construction work underwater or as a foundation

More from Merriam-Webster on caisson

Thesaurus: All synonyms and antonyms for caisson

Nglish: Translation of caisson for Spanish Speakers

Britannica.com: Encyclopedia article about caisson

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