Cubohemioctahedron

The cubohemioctahedron, or cho, is a quasiregular polyhedron and one of 10 uniform hemipolyhedra. It consists of 6 squares and 4 "hemi" hexagons, passing through its center, with two of each joining at a vertex. Its square faces are parallel to those of a cube, and its hemi hexagonal faces are parallel to those of an octahedron: hence the name.

The visible portion of this solid resembles a cuboctahedron with eight tetrahedra carved out. In fact the square faces are the same ones as those of the cuboctahedron, while the hexagons are its equatorial planes.

It is uniform under both cubic and tetrahedral symmetry. In fact it occurs far more often with tetrahedral symmetry in higher uniform polytopes.

Related polyhedra
The great antirhombicosahedron is a uniform polyhedron compound composed of 5 cubohemioctahedra.