<p><strong>Noun</strong></p><ul><li>A watertight structure used in underwater work, consisting of an airtight chamber, open at the bottom and containing air under sufficient pressure to exclude the water.</li><li>A boatlike structure used as a gate for a dock or the like.</li><li>Nautical: Also called camel, pontoon.</li><li>A float for raising a sunken vessel, sunk beside the vessel, made fast to it, and then pumped out to make it buoyant.</li><li>A watertight structure built against a damaged area of a hull to render the hull watertight; cofferdam.</li><li>A two-wheeled wagon used for carrying artillery ammunition.</li><li>An ammunition chest.</li><li>A wooden chest containing bombs or explosives, used formerly as a mine.</li><li>Architecture: coffer.</li></ul>