Decahedron n. : A solid figure or body inclosed by ten plane surfaces.

Example:
How many sides does a Decahedron die have?

Taxonomy
Decahedron, free encyclopedia, Johnson solid, Uniform, Polyhedra, search, band, pyramid, polygons, nonregular, probabilities, d10, Personal tools, Square antiprism, Pentagonal trapezohedron, Interaction, Toolbox, Languages.

Defination from the web:
Decahedron (band) In geometry, a decahedron is a polyhedron with 10 faces. ... A very important decahedron, for its use in role playing games to simulate probabilities, is the Pentagonal trapezohedron, usually known by d10. v • d • e ...