A polyhedron is quasi-regular if it is vertex-transitive and edge-transitive
but not face-transitive. In this context, transitivity means that for any
two vertices (edges, faces) of the polyhedron, there exists a translation,
rotation, and/or reflection that leaves the outward appearance of the
polyhedron unchanged yet moves one vertex (edge, face) to the other.
This definition implies that a quasi-regular polyhedron must have two kinds
of regular faces, where each face of one type is surrounded on all sides by
faces of the other type. There are only two quasi-regular polyhedra that are
not self-intersecting, namely the Cuboctahedron
and the Icosidodecahedron.
When self-intersection is allowed, there are 14 other quasi-regular polyhedra.
Nine have faces that pass through their centers and are often subcategorized
as versi-regular polyhedra [1].
The remaining five are listed on this page.