In Euclidean geometry

Euclidean geometry

Euclidean geometry is a mathematical system attributed to the Alexandrian Greek mathematician Euclid, which he described in his textbook on geometry: the Elements. Euclid's method consists in assuming a small set of intuitively appealing axioms, and deducing many other propositions from these...

 a kite is a quadrilateral

Quadrilateral

In Euclidean plane geometry, a quadrilateral is a polygon with four sides and four vertices or corners. Sometimes, the term quadrangle is used, by analogy with triangle, and sometimes tetragon for consistency with pentagon , hexagon and so on...

 whose four sides can be grouped into two pairs of equal-length sides that are next to each other. In contrast, a parallelogram

Parallelogram

In Euclidean geometry, a parallelogram is a convex quadrilateral with two pairs of parallel sides. The opposite or facing sides of a parallelogram are of equal length and the opposite angles of a parallelogram are of equal measure...

 also has two pairs of equal-length sides, but they are opposite each other rather than next to each other. Kite quadrilaterals are named for the wind-blown, flying kite

Kite

A kite is a tethered aircraft. The necessary lift that makes the kite wing fly is generated when air flows over and under the kite's wing, producing low pressure above the wing and high pressure below it. This deflection also generates horizontal drag along the direction of the wind...

s, which often have this shape and which are in turn named for a bird

Kite (bird)

Kites are raptors with long wings and weak legs which spend a great deal of time soaring. Most feed mainly on carrion but some take various amounts of live prey.They are birds of prey which, along with hawks and eagles, are from the family Accipitridae....

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