A parallelohedron is a space-filling polyhedron that fills space using an infinite number of similarly situated copies (Tutton 1964, pp. 567 and 723; Coxeter 1973, pp. 29-30). There are exactly five "primary"' parallelohedra: the cube, hexagonal prism, elongated dodecahedron, rhombic dodecahedron, and truncated octahedron (Coxeter 1973, p. 29).
The generalization of the cube to a parallelepiped constructed from three line segments that are not all parallel to a common plane is also a parallelohedron.
Parallelohedra are stereohedra, zonohedra, as well as plesiohedra which are space-filling by translation only.
