SCALENOHEDRON
Etymology
Noun
scalenohedron (plural scalenohedrons or scalenohedra)
(geometry, mineralogy, crystallography) A polyhedron having twelve sides, each in the form of a scalene triangle, that is topologically equivalent to a hexagonal bipyramid and whose middle section can be said to inscribe a rhombohedron.
Source: Wiktionary
Sca*le`no*he"dron, n. Etym: [Gr. (Crystallog.)
Definition: A pyramidal form under the rhombohedral system, inclosed by
twelve faces, each a scalene triangle.
Source: Webster’s Unabridged Dictionary 1913 Edition