different between dodecahedron vs pyritohedron

English

Etymology

From Ancient Greek ??????????? (d?dekáedron). Equivalent to dodeca- +? -hedron.

Pronunciation

• (UK) IPA^(key): /?d??d?k??hi?d??n/, /?d??d?k??hi?d??n/
• (US) IPA^(key): /?do?d?k??hi?d??n/

Noun

dodecahedron (plural dodecahedra or dodecahedrons)

1. (geometry) A polyhedron with twelve faces; the regular dodecahedron has regular pentagons as faces and is one of the Platonic solids.
   • 1707, Thomas Blount, Glossographia Anglicana Nova: Or, A Dictionary, Interpreting Such Hard Words, D. Brown, heading DO–DO,

     Dodecahedron, (Gr.) in Geometry, is a solid Figure of 12 Sides or Faces that are regular Pentagons, it is one of the Platonick or Regular Bodies.

   Synonym: duodecahedron

Related terms

Translations

Further reading

• dodecahedron on Wikipedia.Wikipedia

English

Etymology

pyrite +? -o- +? -hedron

Noun

pyritohedron (plural pyritohedra)

1. (mathematics) an irregular dodecahedron, the faces of which are identical but irregular pentagons
2. (mineralogy) the shape of one of the crystal habits of pyrite