a ski on which to water-ski, designed to plane over water: it is shorter and broader than the ski used on snow.
wa•ter-skiPronunciation: (wô'tur-skē", wot'ur-), [key]
—v.i., -skied, -ski•ing.
to plane over water on water skis or a water ski by grasping a towing rope pulled by a speedboat.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.