Platonic solid: Meaning and Definition of

Platon'ic sol'id

Pronunciation: [key]
— Geom. Geom.
  1. one of the five regular polyhedrons: tetrahedron, octahedron, hexahedron, icosahedron, or dodecahedron.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.