'hydrosulphurous acid' definitions:

Definition of 'hydrosulphurous acid'

From: GCIDE

Hyposulphurous \Hy`po*sul"phur*ous\, a. [Pref. hypo- + sulphurous.] (Chem.) Pertaining to, or containing, sulphur, all, or a part, in a low state of oxidation. [1913 Webster]
Hyposulphurous acid. (a) Thiosulphuric acid. [Obs.] (b) An acid, H2SO2, obtained by the reduction of sulphurous acid. It is not obtained in the free state, but in an orange-yellow water solution, which is a strong reducing and bleaching agent. Called also hydrosulphurous acid. [1913 Webster]