Antiprism

An antiprism is a polytope built from two parallel bases, dual to one another. The bases are joined to each other by various duopyramidal facets which link corresponding elements together. Antiprisms generalize the concept of a polygonal antiprism to higher (and lower) dimensions.

Under this definition, the octahedron atop cube segmentochoron can be seen as a cubic antiprism or an octahedral antiprism, and the hexadecachoron can be seen a tetrahedral antiprism. Unless their bases are self-dual, as happens with the simplex cases, which produce cross polytopes, and with the 5D icositetrachoric antiprism, these antiprisms are generally not isogonal, and unless their bases are regular, they are not even CRF. However, their simple mathematical definition and their relation to more general laces makes them worthwhile to study.