oc·ta·he·drite \ˌäktəˈhēˌdrīt\noun (-s) Etymology: French octaédrite, from octaèdre octahedron (from Greek oktaedron) + -ite 1.: anatase 2.: an iron meteorite having plates of kamacite with narrow selvages of taenite and interstitial plessite constituting a very intimate mixture of kamacite and taenite — compare widmannstaetten figures