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

Bally’s expected to finish demolition in January and begin driving foundational caissons into the ground this month, with the permanent casino targeted for a September 2026 opening. —Robert Channick, Chicago Tribune, 10 Feb. 2025

The Army hired experts for advice that ranged from finding the right horses for caisson duty to designing the curriculum for soldiers who care and ride them. —John Bacon, USA TODAY, 7 Jan. 2025

Construction will then begin with the installation of caissons as a foundation for the casino by early February. —Robert Channick, Chicago Tribune, 9 Jan. 2025

The Army suspended the Caisson Detachment operation in May 2023 following the deaths of two horses used to haul caissons in funerals at Arlington National Cemetery. —John Bacon, USA TODAY, 7 Jan. 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

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