adjective
: of or characterized by the symmetry of the class of crystals in the hexagonal system having a vertical hexad axis, six horizontal diad axes, six vertical planes, and a horizontal plane of symmetry
adjective
: of or characterized by the symmetry of the class of crystals in the hexagonal system having a vertical hexad axis, six horizontal diad axes, six vertical planes, and a horizontal plane of symmetry
Webster's New International English Dictionary. Новый международный словарь английского языка Webster. 2012