noun

1. a chest for holding ammunition
2. a two-wheeled wagon for transporting ammunition
3. a watertight enclosure inside which underwater construction work can be done
4. a watertight box for raising sunken ships: after the box is sunk and attached, the water is forced out of it so that it floats
5. a hollow, boat-shaped box, used as a floodgate at a dock or basin

Etymology: Fr < It cassone < cassa, a chest < L capsa, a box, case