rhombohedron

{| class="wikitable" align="right" style="margin-left:10px" width="250" !bgcolor=#e7dcc3 colspan=2|Rhombohedron |- |align=center colspan=2|240px|Rhombohedron |- |bgcolor=#e7dcc3|Type||prism |- |bgcolor=#e7dcc3|Faces||6 rhombi |- |bgcolor=#e7dcc3|Edges||12 |- |bgcolor=#e7dcc3|Vertices||8 |- |bgcolor=#e7dcc3|Symmetry group||Ci , [2+,2+], (×), order 2 |- |bgcolor=#e7dcc3|Properties||convex, equilateral, zonohedron, parallelohedron |}

In geometry, a rhombohedron (also called a rhombic hexahedron or, inaccurately, a rhomboid) is a special case of a parallelepiped in which all six faces are congruent rhombi. It can be used to define the rhombohedral lattice system, a honeycomb with rhombohedral cells. A rhombohedron has two opposite apices at which all face angles are equal; a prolate rhombohedron has this common angle acute, and an oblate rhombohedron has an obtuse angle at these vertices. A cube is a special case of a rhombohedron with all sides square.