Definition of "free-board" []

• Nautical, the part of the side of a vessel or boat which lies between the line of flotation and the upper side of the deck (or a point corresponding to it), or, when there are several decks, of the uppermost watertight deck. (noun)
• The minimum free-board to which British merchant vessels may be loaded is indicated by a mark known as the Plimsoll mark. Lloyd's Register is empowered to assign the deepest water-line to which a vessel may be loaded. The lines must be permanently marked on the side of the vessel, as shown in the cut. F W is the fresh-water free-board line to which the ship can be loaded in a fresh-water harbor. S is the corresponding summer load-line for the same displacement in salt water. W is the winter free-board line. WNA is the winter free-board line for voyages in the North Atlantic. I S is the line for summer voyages in the Indian Ocean. L R is Lloyd's Register. For sailing-vessels the FW and WNA lines only are marked. (noun)

The Century Dictionary (Public Domain)

• "His instinct was to call them out of the chasm now - there was already less than twelve inches of free-board at the top of the wall."
• "Her low free-board indicated that she was heavily cargoed."
• "In another instant the rowers shipped their oars and the gunwale scraped along the free-board of the schooner."