n. Milit.: A wooden chest into which several bombs are put, and sometimes gunpowder, to be exploded in the way of an enemy or under some work of which he has gained possession.n. An ammunition-wagon; also, an ammunition-chest.n. In architecture, a sunken panel in a coffered ceiling or in the soffit of Roman or Renaissance architecture, etc.; a coffer; a lacunar. See cut under coffer.n. In civil engineering: A vessel in the form of a boat, used as a flood-gate in docks.n. An apparatus on which vessels may be raised and floated; especially, a kind of floating dock, which may be sunk and floated under a vessel's keel, used for docking vessels at their moorings, without removing stores or masts. (See floating dock, under dock.)n. A water-tight box or casing used in founding and building structures in water too deep for a coffer-dam, such as piers of bridges, quays, etc.