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Platonic solid

noun Geometry.
  1. one of the five regular polyhedrons: tetrahedron, octahedron, hexahedron, icosahedron, or dodecahedron.

Origin of Platonic solid

First recorded in 1950–55
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for platonic solid

Platonic solid

noun
  1. any of the five possible regular polyhedra: cube, tetrahedron, octahedron, icosahedron, and dodecahedronAlso called (esp formerly): Platonic body

Word Origin for Platonic solid

C17: named after Plato 1, who was the first to list them
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012