Wordnet 3.0
NOUN (1)
1. 
 any one of five solids whose faces are congruent regular polygons and whose polyhedral angles are all congruent; 
[syn: regular polyhedron, regular convex solid, regular convex polyhedron, Platonic body, Platonic solid, ideal solid]
WordNet (r) 3.0 (2006):
Platonic solid
    n 1: any one of five solids whose faces are congruent regular
         polygons and whose polyhedral angles are all congruent
         [syn: regular polyhedron, regular convex solid,
         regular convex polyhedron, Platonic body, Platonic
         solid, ideal solid]