Octahemioctahedron

The octahemioctahedron, or oho, is a quasiregular polyhedron and one of 10 uniform hemipolyhedra. It consists of 8 equilateral triangles and 4 "hemi" hexagons passing through its center, with two of each joining at a vertex. Its triangular faces, as well as its hemi hexagonal faces, are parallel to those of an octahedron: hence the name.

Unlike the other quasiregular hemipolyhedra, the octahemioctahedron is orientable. This is because the triangles can be grouped into two sets of four, one of which is seen as positive-density and the other seen as negative-density.

The visible portion of this solid resembles a cuboctahedron with six square pyramids carved out. In fact the triangular faces are the same ones as from the cuboctahedron, while the hexagons are those of the cuboctahedron's equatorial planes.

Tetratetratetrahedron
The octahemioctahedron can also be constructed with A3 (tetrahedral) symmetry and can be called a tetratetratetrahedron or tristetrahedron.

Related polyhedra
The icosidisicosahedron is a uniform polyhedron compound composed of 5 octahemioctahedra.