The Collaborative International Dictionary of English v.0.48:

Bisulphide \Bi*sul"phide\, n. [Pref. bi- + sulphide.] (Chem.)
   A sulphide having two atoms of sulphur in the molecule; a
   disulphide, as in iron pyrites, FeS2; -- less frequently
   called bisulphuret.
   [1913 Webster]