The Collaborative International Dictionary
Leucoxene
Leucoxene \Leu*cox"ene\ (l[-u]*k[o^]ks"[=e]n), n. [Leuco- + Gr. xe`nos stranger.] (Min.) A nearly opaque white mineral, in part identical with titanite, observed in some igneous rocks as the result of the alteration of titanic iron.
Wiktionary
leucoxene
n. (context mineralogy English) A mineral, mostly composed of rutile, occurring in igneous rocks, often by alteration of ilmenite or other titanium minerals