A hydroplane is an aircraft that's designed to land on water, or a boat that skims lightly across the water's surface. When you hydroplane, it's more likely to be in a car that's slipping on a wet road.

The noun hydroplane always refers to a vehicle, either a speedboat that seems to hover over the surface of water as it travels, or a plane that can take off and land on an ocean or lake. Used as a verb, hydroplane describes what these vehicles do — or what a fast-moving car does on a very wet surface, losing traction as it begins to float and slide. The prefix hydro- means "water" in Greek.

Definitions of hydroplane
  1. noun
    an airplane that can land on or take off from water
    “the designer of marine aircraft demonstrated his newest hydroplane
    synonyms: seaplane
    see moresee less
    floatplane, pontoon plane
    a seaplane equipped with pontoons for landing or taking off from water
    flying boat
    a large seaplane that floats with its fuselage in the water rather than on pontoons
    type of:
    aeroplane, airplane, plane
    an aircraft that has a fixed wing and is powered by propellers or jets
  2. noun
    a speedboat that is equipped with winglike structures that lift it so that it skims the water at high speeds
    “the museum houses a replica of the jet hydroplane that broke the record”
    synonyms: hydrofoil
    see moresee less
    type of:
    a fast motorboat
  3. verb
    glide on the water in a hydroplane
    synonyms: seaplane
    see moresee less
    type of:
    aviate, fly, pilot
    operate an airplane
Word Family

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