caisson

noun

cais·​son ˈkā-ˌsän 

-sᵊn

British also kə-ˈsün

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

• caisson 1b

Examples of caisson in a Sentence

Recent Examples on the Web

In 2024, Bally’s had to relocate the 34-story hotel tower, which is beginning to rise up over the Ohio feeder ramp, to the south end of the casino after it was determined that driving caissons into the ground might damage municipal water management infrastructure pipes along the river. —Robert Channick, Chicago Tribune, 15 Jan. 2026

Built in 2009 on 75 bedrock-deep caissons, the 7,681-square-foot house offers five bedrooms and eight bathrooms. —Sandra Barrera, Oc Register, 18 Nov. 2025

In June 2025, the caisson program restarted following an $18 million overhaul by the Army. —Andrew Paul, Popular Science, 9 July 2025

Cotton said the caisson ceremony holds special meaning for relatives of the fallen. —Tom Vanden Brook, USA Today, 27 May 2025

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

Phrases Containing caisson

• caisson disease

Rhymes for caisson

• basin
• chasten
• hasten
• jason
• capsaicin
• freemason
• stonemason
• subbasin
• washbasin
• indomethacin

Kids Definition

caisson

noun

cais·​son ˈkā-ˌsän 

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