In Euclidean geometry, a kite is a quadrilateral with reflection symmetry across a diagonal. Because of this symmetry, a kite has two equal angles and two pairs of adjacent equal-length sides. Kites are also known as deltoids, but the word deltoid may also refer to a deltoid curve, an unrelated geometric object sometimes studied in connection with quadrilaterals. A kite may also be called a dart, particularly if it is not convex.
Ten-sided dice
Image: Rhombicdodecahedron
Image: Deltoidalicositetrahedron
Image: Deltoidalhexecontahedron
In mathematics, reflection symmetry, line symmetry, mirror symmetry, or mirror-image symmetry is symmetry with respect to a reflection. That is, a figure which does not change upon undergoing a reflection has reflectional symmetry.
Many animals, such as this spider crab Maja crispata, are bilaterally symmetric.
Mirror symmetry is often used in architecture, as in the facade of Santa Maria Novella, Florence, 1470.