Wakeboard

n. short and very wide buoyant board ridden by a person in the same way as a surfboard and pulled by a motorboat

Wakeboarding is a surface water sport which involves riding a wakeboard over the surface of a body of water behind a boat. It was developed from a combination of water skiing, snow boarding and surfing techniques.The rider is towed behind a boat; typically at speeds of 18-24 miles per hour depending on water conditions, rider's weight, board size, and all depending on the riders comfort speed. But wakeboarding can also be performed on a variety of media including closed-course cables, winches, PWCs, and ATVs.
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Noun
1. a buoyant board (resembling a surfboard) that is used to ride over water while being pulled behind a motorboat
(synonym) wake board
(hypernym) board