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.