[1] : The Collaborative International Dictionary of English v.0.48

icosahedron \i`cosahe"dron\, n. gr. ?; ? twenty + ? seat,
   base, fr. ? to sit. geom.
   a solid bounded by twenty sides or faces.
   1913 webster

   regular icosahedron, one of the five regular polyhedrons,
      bounded by twenty equilateral triangules. five triangles
      meet to form each solid angle of the polyhedron.
      1913 webster
see also:
regular icosahedron 

[2] : WordNet (r) 2.0

icosahedron
     n : any polyhedron having twenty plane faces
     also: icosahedra pl
see also:
icosahedra 

Icosahedron >> I Words
Icosahedron, definition of term: Icosahedron
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