A monogonal dihedron is a 3-D polyhedron with two monogonal faces which share an edge and a vertex. In normal Euclidean space, it is degenerate, but can exist as a tiling of the sphere where each face makes up a hemisphere.
A monogonal dihedron is a 3-D polyhedron with two monogonal faces which share an edge and a vertex. In normal Euclidean space, it is degenerate, but can exist as a tiling of the sphere where each face makes up a hemisphere.