16-cell , runcitruncated 24-cell , omnitruncated 24-cell , omnitruncated 120-cell , runcitruncated 600-cell . Triangular prism In geometry , a triangular prism is a three-sided prism ; it is a polyhedron made of a triangular base, a translated copy, and 3 faces joining corresponding sides. Equivalently, it is a pentahedron of