Caisson

·noun A chest to hold ammunition.

II. Caisson ·noun A sunk panel of ceilings or soffits.

III. Caisson ·noun A structure, usually with an air chamber, placed beneath a vessel to lift or float it.

IV. Caisson ·noun A hollow floating box, usually of iron, which serves to close the entrances of docks and basins.

V. Caisson ·noun A chest filled with explosive materials, to be laid in the way of an enemy and exploded on his approach.

VI. Caisson ·noun A water-tight box, of timber or iron within which work is carried on in building foundations or structures below the water level.

VII. Caisson ·noun A four-wheeled carriage for conveying ammunition, consisting of two parts, a body and a limber. In light field batteries there is one caisson to each piece, having two ammunition boxes on the body, and one on the limber.