\Hy`po*sul*phur"ic\, a. [Pref. hypo- + sulphuric.]
(Chem.)
Pertaining to, or containing, sulphur in a lower state of
oxidation than in the sulphuric compounds; as, hyposulphuric
acid.
{Hyposulphuric acid}, an acid, {H2S2O6}, obtained by the
   action of manganese dioxide on sulphur dioxide, and known
   only in a watery solution and in its salts; -- called also
   {dithionic acid}. See {Dithionic}.