Definitions for "Plimsoll Mark"
A series of horizontal lines, corresponding to the seasons of the year and fresh or saltwater, painted on the outside of a ship marking the level which must remain above the surface of the water for the vessel's stability.
A mark indicating up to which limit a ship may be loaded. It is welded on both sides of the ship. Its height depends on the gravity of the water in which the ship is situated.
A series of horizontal lines welded on the hull on both sides of a vessel. The lines indicate the limit to which the vessel can safely be loaded, depending on the seasons of the year and whether the vessel is in saltwater or freshwater. Letters indicating the name of the vessel's classification society are also incorporated into the plimsoll mark. Synonym: load lines.