- a structure projecting from the side or main deck of a vessel to support a gun or the outer edge of a paddle box.
- a buoyant appendage at the gunwale of a canoe to resist capsizing.
- a protuberance at the side of a flying-boat hull, designed to increase lateral stability in the water.
- an outboard support for a gun enabling it to fire fore and aft
- a semicircular gun turret on the side of a tank
- a float or flotation chamber along the gunwale of a boat or ship
- a structural projection from the side of a paddle steamer for supporting a paddle wheel
- a structural unit attached to a helicopter fuselage by fixed struts, housing the main landing gear and inflatable flotation bags
