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n. An airplane having two pairs of wings fixed at different levels, especially one above and one below the fuselage.

n. An airplane that has two pairs of wings, one above the other

n. An aëroplane with two main supporting surfaces one above the other.

adj. Having, or consisting of, two superposed planes, aërocurves, or the like; of or pertaining to a biplane.

n. In mathematics, the pair of coincident planes to which the tangent cone of a node reduces, when that node is a binode.

n. A flying- or a gliding-machine in which two principal superposed aëroplane surfaces are depended upon to sustain the machine in the air.

n. old fashioned airplane; has two wings one above the other

"The Gilmore house earned its “airplane” nickname immediately, both because of its shape, looking like a biplane from the east, and because of its location, which made it appear that the "plane" was about to take off over the city of Madison."

plane    aeroplane    airplane   

triplane    monoplane   

monoplane    scouter    turboprops    seaplane    rock'n'roll    cantilever    leaf-shaped    low-wing    hovercraft    barrette