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.

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