A plane is a vehicle that flies through the air, but it is also a tool used to make something smooth and flat, a kind of tree or a level surface. As a verb, to plane something is to make it flat and smooth.

Don't confuse plane with plain, an adjective that means "simple" or a noun that means "flat land," like the plains of the American Midwest. This can be tricky because plane describes something that is flat and level, or the tool or action that makes something flat and level. If you remember that plain applies only to landforms, the difference will be plain to see — meaning obvious.

Definitions of plane
  1. noun
    (mathematics) an unbounded two-dimensional shape
    “we will refer to the plane of the graph as the X-Y plane”
    “any line joining two points on a plane lies wholly on that plane”
    synonyms: sheet
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    Cartesian plane
    a plane in which all points can be described in Cartesian coordinates
    facet plane
    the plane of a facet of an object (as of a cube)
    midline, midplane
    the median plane of the body (or some part of the body)
    orbital plane
    (astronomy) the plane on which a body is orbiting
    picture plane
    the plane that is in the foreground of a drawing or painting; coextensive with but different from the objective surface of the work
    tangent plane
    the plane that contains all the lines tangent to a specific point on a surface
    type of:
    form, shape
    the spatial arrangement of something as distinct from its substance
  2. noun
    a level of existence or development
    “he lived on a worldly plane
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    type of:
    degree, level, point, stage
    a specific identifiable position in a continuum or series or especially in a process
  3. noun
    an aircraft that has a fixed wing and is powered by propellers or jets
    synonyms: aeroplane, airplane
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    United States military aircraft; B- stands for bomber
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    a commercial airplane that carries passengers
    amphibian, amphibious aircraft
    an airplane designed to take off and land on water
    old fashioned airplane; has two wings one above the other
    a military aircraft that drops bombs during flight
    delta wing
    an airplane with wings that give it the appearance of an isosceles triangle
    attack aircraft, fighter, fighter aircraft
    a high-speed military or naval airplane designed to destroy enemy aircraft in the air
    hangar queen
    an airplane with a bad maintenance record
    jet, jet plane, jet-propelled plane
    an airplane powered by one or more jet engines
    an airplane with a single wing
    multiengine airplane, multiengine plane
    a plane with two or more engines
    propeller plane
    an airplane that is driven by a propeller
    reconnaissance plane
    a military airplane used to gain information about an enemy
    hydroplane, seaplane
    an airplane that can land on or take off from water
    an airplane equipped with skis so it can land on a snowfield
    tanker plane
    an airplane constructed to transport chemicals that can be dropped in order to fight a forest fire
    a subsonic jet airliner operated over short distances
    dive bomber
    a bomber that releases its bombs during a steep dive toward the target
    double-prop, double-propeller plane, twin-prop, twin-propeller-plane
    a propeller plane with an engine that drives two propellers in opposite directions (for stability)
    fan-jet, fanjet, turbofan, turbojet
    an airplane propelled by a fanjet engine
    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
    a fast maneuverable fighter plane designed to intercept enemy aircraft
    a large jet plane that carries passengers
    jumbo jet, jumbojet
    a very large jet plane
    a fighter plane used for suicide missions by Japanese pilots in World War II
    narrow-body, narrow-body aircraft, narrowbody aircraft
    a commercial airliner with a single aisle
    propjet, turbo-propeller plane, turboprop
    an airplane with an external propeller that is driven by a turbojet engine
    single prop, single-propeller plane
    a propeller plane with a single propeller
    stealth bomber
    a bomber that is difficult to detect by radar
    stealth fighter
    a fighter that is difficult to detect by radar; is built for precise targeting and uses laser-guided bombs
    a jet plane propelled by two jet engines
    twin-aisle airplane, wide-body, wide-body aircraft, widebody aircraft
    a commercial airliner with two aisles
    type of:
    heavier-than-air craft
    a non-buoyant aircraft that requires a source of power to hold it aloft and to propel it
  4. verb
    travel on the surface of water
    synonyms: skim
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    ride on an aquaplane
    rise up onto a thin film of water between the tires and road so that there is no more contact with the road
    type of:
    move smoothly and effortlessly
  5. noun
    a carpenter's hand tool with an adjustable blade for smoothing or shaping wood
    “the cabinetmaker used a plane for the finish work”
    synonyms: carpenter's plane, woodworking plane
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    beading plane
    a plane with a concave blade for making moulding with beadwork
    block plane
    a small plane used on end grains of wood
    bullnose, bullnosed plane
    a small carpenter's plane with the cutting edge near the front
    chamfer plane
    a plane that makes a beveled edge
    circular plane, compass plane
    a plane with a flexible face that can plane concave or convex surfaces
    combination plane
    a woodworking plane that has interchangeable cutters of various shapes
    dovetail plane
    a woodworking plane designed to make the grooves for dovetail joints
    fore plane
    a carpenter's plane intermediate between a jack plane and a jointer plane
    jack plane
    a carpenter's plane for rough finishing
    jointer, jointer plane, jointing plane, long plane
    a long carpenter's plane used to shape the edges of boards so they will fit together
    match plane, tonguing and grooving plane
    a plane having cutters designed to make the tongues and grooves on the edges of matchboards
    openside plane, rabbet plane
    a woodworking plane designed to cut rabbets
    router plane
    a woodworking plane with a narrow cutting head that will make grooves with smooth bottoms
    scrub plane
    a narrow woodworking plane used to cut away excess stock
    smooth plane, smoothing plane
    a small plane for finish work
    a small plane that has a handle on each side of its blade; used for shaping or smoothing cylindrical wooden surfaces (originally wheel spokes)
    dado plane
    a plane for making a dado groove
    type of:
    edge tool
    any cutting tool with a sharp cutting edge (as a chisel or knife or plane or gouge)
    hand tool
    a tool used with workers' hands
  6. noun
    a power tool for smoothing or shaping wood
    synonyms: planer, planing machine
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    type of:
    power tool
    a tool driven by a motor
  7. verb
    cut or remove with or as if with a plane
    synonyms: shave
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    type of:
    separate with or as if with an instrument
  8. verb
    make even or smooth, with or as with a carpenter's plane
    plane the top of the door”
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    type of:
    smooth, smoothen
    make smooth or smoother, as if by rubbing
  9. adjective
    having a surface without slope, tilt in which no part is higher or lower than another
    “a plane surface”
    synonyms: flat, level
    being level or straight or regular and without variation as e.g. in shape or texture; or being in the same plane or at the same height as something else (i.e. even with)
Word Family

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