Small barrels for containing water or other liquids; they are also used in watering the ship as gang-casks. (See bareka.) Also, those billows which break violently over reefs, rocks, or shallows, lying immediately at, or under, the surface of the sea. They are distinguished both by their appearance and sound, as they cover that part of the sea with a perpetual foam, and produce loud roaring, very different from what the waves usually have over a deeper bottom. Also, a name given to those rocks which occasion the waves to break over them.