Small icosihemidodecahedron

The small icosihemidodecahedron, or seihid, is a quasiregular polyhedron and one of 10 uniform hemipolyhedra. It consists of 20 equilateral triangles and 6 central decagons, with two of each joining at a vertex. Its triangular faces are parallel to those of an icosahedron, and its hemi decagonal faces are parallel to those of a dodecahedron: hence the name "icosihemidodecahedron". The "small" suffix, used for stellations in general, distinguishes it from the great icosihemidodecahedron, which also has this face arrangement.

It is a faceting of the icosidodecahedron, keeping the original's triangles while also using its equatorial decagons.