The Collaborative International Dictionary
Octahedral iron ore
Octahedral \Oc`ta*he"dral\, a. [See Octahedron.] Having eight faces or sides; of, pertaining to, or formed in, octahedrons; as, octahedral cleavage; an octahedral crystal.
Octahedral borax (Chem.), borax obtained from a saturated solution in octahedral crystals, which contain five molecules of water of crystallization; distinguished from common or prismatic borax.
Octahedral iron ore (Min.), magnetite.