Polytetrahedron is a term used for three distinct types of objects, all based
on the
tetrahedron:
A
uniform convex 4-polytope made up of 600
tetrahedralcells. It is more commonly known as a 600-cell or hexacosichoron. Other derivative 4-polytope are identified as polytetrahedra, where a qualifying prefix such as rectified or truncated is used.
A connected set of
regular tetrahedra, the 3-dimensional analogue of a
polyiamond. Polytetrahedra and polyiamonds are related as
polycubes are related to
polyominoes.
In
origami, a polypolyhedron is "a compound of multiple linked
polyhedral skeletons with
uniform nonintersecting edges"
[1]. There exist two topologically distinct polytetrahedra, each made up of four intersecting
triangles.