Meaning of POLYHEDRON in English


In Euclidean geometry , a three-dimensional object composed of a finite number of polygonal surfaces (faces).

Technically, a polyhedron is the boundary between the interior and exterior of a solid. In general, polyhedrons are named according to number of faces. A tetrahedron has four faces, a pentahedron five, and so on; a cube is a six-sided regular polyhedron (hexahedron) whose faces are squares. The faces meet at line segments called edges, which meet at points called vertices. See also Platonic solid ; Euler's formula .

Britannica English dictionary.      Английский словарь Британика.