The Collaborative International Dictionary
Ethionic acid
Ethionic \Eth`i*on"ic\, a. [Ethyl + thionic.] (Chem.) Pertaining to, derived from, or designating, an acid so called.
Ethionic acid (Chem.), a liquid derivative of ethylsulphuric and sulphuric (thionic) acids, obtained by the action of sulphur trioxide on absolute alcohol.
Wiktionary
ethionic acid
n. (context chemistry English) A liquid derivative of ethylsulphuric acid and sulphuric acid, obtained by the action of sulphur trioxide on absolute alcohol.