Platonic solid

Any of the five regular polyhedra

In geometry, a Platonic solid is a convex, regular polyhedron in three-dimensional Euclidean space. Being a regular polyhedron means that the faces are congruent (identical in shape and size) regular polygons (all angles congruent and all edges congruent), and the same number of faces meet at each vertex. There are only five such polyhedra: the regular tetrahedron (four triangular faces), the cube (six square faces), the regular octahedron (eight triangular faces), the regular dodecahedron (twelve pentagonal faces), and the regular icosahedron (twenty triangular faces).

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