a hard, brittle, orthorhombic pyroxene, MgSiO, found in igneous rocks and in meteorites; magnesium silicate
See enstatite in American Heritage Dictionary 4
(ĕnˈstə-tītˌ)
noun
A glassy, usually yellowish gray variety of orthorhombic pyroxene having a magnesium silicate base, mainly MgSiO3, usually found embedded in igneous rocks and meteorites.