What is a 120-cell?

A 120-cell is a finite regular four-dimensional polytope with the schlafli symbol 5,3,3 . It is also known as hyperdodecahedron or hecatonicosachorn and is composed of 120 docahedra, hence it is known as 120-cell. The 120-cell has 600 vertices, 720 pentagons and 11,200 edges. It is one of the six regular polychora.