octahedral

Having eight plane surfaces.

Having eight equal surfaces or faces.

Having eight faces or sides; of, pertaining to, or formed in, octahedrons.

borax obtained from a saturated solution in octahedral crystals, which contain five molecules of water of crystallization; distinguished from common or prismatic borax.

magnetite.

Having eight plane surfaces; thus, in the shape or form of an octahedron.

Of, or pertaining to octahedra.