tetroxide
Tet*rox"ide, n. Etym: [Tetra- + oxide.] (Chem.) Defn: An oxide having four atoms of oxygen in the molecule; a quadroxide; as, osmium tetroxide, OsO.
Tet*rox"ide, n. Etym: [Tetra- + oxide.] (Chem.) Defn: An oxide having four atoms of oxygen in the molecule; a quadroxide; as, osmium tetroxide, OsO.