plesiohedron

== English == === Etymology === From plesio- +‎ -hedron. === Pronunciation === === Noun === plesiohedron (plural plesiohedra) (geometry) A special kind of space-filling polyhedron, defined as the Voronoi cell of a symmetric Delone set. Three-dimensional Euclidean space can be completely filled by copies of any one of these shapes, with no overlaps.