Definition:Pentagonal Bipyramid

Definition
A pentagonal bipyramid is a polyhedron formed by taking two pyramids whose bases are regular pentagons and whose other faces are equilateral triangles, and placing their bases together:


 * PentagonalBipyramid.png

The pentagonal bipyramid is an example of a deltahedron.

Also defined as
A pentagonal bipyramid can also be defined as the bipyramid formed by placing general pyramids with congruent pentagonal bases) together, but this is rarely seen.

Also known as
The term pentagonal dipyramid can be found at least as frequently as pentagonal bipyramid.