dihedron (dihedron)

[ B D Dihedral Angle. diheliost, diheliumt (di-he'li-os, -um), n. [NL., dihexahedron (di-hek-sa-hedron), n.; pl. di hexahedrons, dihexahedra (-drons, -dra). [ Dihexahedra of quartz, and various rare minerals are noted in them. Amer . Naturalist , XXII. 247.