noun1. navyan outboard support for a gun enabling it to fire fore and aft
2. a semicircular gun turret on the side of a tank
3. a float or flotation chamber along the gunwale of a boat or ship
4. a structural projection from the side of a paddle steamer for supporting a paddle wheel
5. a structural unit attached to a helicopter fuselage by fixed struts, housing the main landing gear and inflatable flotation bags