In geometry, a rhombohedron is a three-dimensional figure like a cube, except that its faces are not squares but rhombi. It is a special case of a parallelepiped where all edges are the same length.

In general the rhombohedron can have three types of rhombus faces in congruent opposite pairs.

If all of the non-obtuse internal angles of the faces are equal, it can be called a trigonal trapezohedron.

Another special case is that, where there is a plane of symmetry through four vertices (with symmetry group C_2h), and a special case of that, where there is another plane of symmetry through the other four vertices (with symmetry group D_2h).

The cube combines these special properties.

See also

• Rhombohedral - crystal system

Prismatoid polyhedra | Zonohedra

Rhomboèdre | Ромбоэдр