noun1. a watertight chamber open at the bottom and containing air under pressure, used to carry out construction work under water
2. a similar unpressurized chamber
3. a watertight float filled with air, used to raise sunken ships
See also camel (sense 2) 4. a watertight structure placed across the entrance of a basin, dry dock, etc, to exclude water from it
5. a. a box containing explosives, formerly used as a mine
c. a two-wheeled vehicle containing an ammunition chest
6. another name for coffer (sense 3)
Word origin
C18: from French, assimilated to
caisse case2