a. [ Pref. di- + -thionic. ] (Chem.) Containing two equivalents of sulphur; as, dithionic acid. [ 1913 Webster ]

Dithionic acid (Chem.), an unstable substance, H2S2O6, known only in its solutions, and in certain well-defined salts. [ 1913 Webster ]

a. [ Ethyl + thionic. ] (Chem.) Pertaining to, derived from, or designating, an acid so called. [ 1913 Webster ]

Ethionic acid (Chem.), a liquid derivative of ethylsulphuric and sulphuric (thionic) acids, obtained by the action of sulphur trioxide on absolute alcohol.

a. [ Is- + ethionic. ] (Chem.) Pertaining to, derived from, or designating, an acid, HO.C2H4.SO3H, obtained as an oily or crystalline substance, by the action of sulphur trioxide on alcohol or ether. It is derivative of sulphuric acid. [ 1913 Webster ]

a. [ Methyl + thionic. ] (Chem.) Of, pertaining to, or designating, a sulphonic (thionic) acid derivative of methane, obtained as a stable white crystalline substance, CH2.(SO3H)2, which forms well defined salts. [ 1913 Webster ]

a. [ Gr. o'i^nos wine + thionic. ] (Chem.) Pertaining to an acid now called sulphovinic acid or ethyl sulphuric acid. [ 1913 Webster ]

a. [ Penta- + thionic. ] (Chem.) Pertaining to, or designating, an acid of sulphur obtained by leading hydrogen sulphide into a solution of sulphur dioxide; -- so called because it contains five atoms of sulphur. [ 1913 Webster ]

a. [ Tetra- + thionic. ] (Chem.) Of, pertaining to, or designating, a thionic derivative, H2S4O6, of sulphuric acid, obtained as a colorless, odorless liquid. [ 1913 Webster ]

a. [ Gr. &unr_; brimstone, sulphur. ] (Chem.) Of or pertaining to sulphur; containing or resembling sulphur; specifically, designating certain of the thio compounds; as, the thionic acids. Cf. Dithionic, Trithionic, Tetrathionic, etc. [ 1913 Webster ]

a. [ Pref. tri- + thionic. ] (Chem.) Of or pertaining to, or designating, a certain thionic acid, H2S3O6 which is obtained as a colorless, odorless liquid. [ 1913 Webster ]