Dithionic \Di`thi*on"ic\, a. [Pref. di- + -thionic.] (Chem.)
Containing two equivalents of sulphur; as, dithionic acid.
{Dithionic acid} (Chem.), an unstable substance, {H2S2O6},
known only in its solutions, and in certain well-defined
salts.