a vehicle that travels just above the surface of land or water on a cushion of air provided by a downward jet from its engines, propellers, etc.
See air-cushion vehicle in American Heritage Dictionary 4
noun Abbr. ACV
A usually propeller-driven vehicle designed for traveling over land or water on a supportive cushion of slowly moving, low-pressure air. Also called ground-effect machine, hovercraft.
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air-cushion vehicle
front cutaway view of a flexible skirt model hovercraft