The name of this geometric figure contains the answer to this question. Dōdeka in the Greek language means "twelve" and hédra means "base" or "face". So, it is a polyhedron with twelve flat faces.

Besides a regular dodecahedron which has 12 faces as regular pentagons, there are many other types of dodecahedra. All of them are characterized by icosahedral symmetry, order 120.

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