Freeboard

• Sporting Goods. The six-wheeled skateboard which acts like a snowboard (on pavement).
• Nautical. The distance from the waterline
  Waterline
  
  The waterline is an imaginary line marking the level at which a ship or boat floats in the water. To an observer on the ship the water appears to rise or fall against the Hull ....
   to the upper deck
  Deck (ship)
  
  A deck is a permanent covering over a compartment or a hull of a ship. On a deck #Glossary or deck #Glossary, the primary deck is the horizontal structure which forms the 'roof' for the hull, which both strengthens the hull and serves as the primary working surface....
   level, measured at the lowest point where water can enter the boat
  Boat
  
  A boat is a watercraft of modest size designed to float or plane on water, and provide transport over it. Usually this water will be inland or in protected coastal areas....
   or ship
  Ship
  
  A ship is a large watercraft that floats on water. Ships are generally distinguished from boats based on size. Ships may be found on lakes, seas, and rivers and they allow for a variety of activities, such as the ferry or cargo ships, fishing, cruise ship, Coast guard, and warship....
  .
• Civil Engineering The meaning for commercial vessels. The amount of watertight surface between a given level of lake, sea or river water and the lowest possible entry point during flooding or large waves.
• Water channel Design. The distance from the water level to the top of the channel's sides.
• Freeboard is also used to describe the height of an ice floe above the water surface. Freeboard does not include the potential snow coverage on the ice floe.

Sporting Goods