*dodecahedron*

n. [ Gr. &unr_;; &unr_; twelve + &unr_; seat, bottom, base: cf. F. dodécaèdre. ] (Geom. & Crystallog.) A solid having twelve faces. [ 1913 Webster ]

☞ The regular dodecahedron is bounded by twelve equal and regular pentagons; the pyritohedron (see Pyritohedron) is related to it; the rhombic dodecahedron is bounded by twelve equal rhombic faces. [ 1913 Webster ]