\▐bók-▐sīt, ▐bäk-\ n [F bauxite, from Les Baux] (1861) Al2O3.2H2O. Aluminum mineral, consisting chiefly of a hydrated aluminum oxide. The color of native bauxite may be white, brownish red, or grey. Used as the source of many aluminum compounds. Crude powdered bauxite has been used to some extent as filler for paints.