/ Dictionary / Index T thiosulfuric acid: Meaning and Definition of Find definitions for: thi'osulfu'ric ac'id Pronunciation: [key] — Chem. Chem. an acid, HSO, that may be regarded as sulfuric acid with one oxygen atom replaced by sulfur. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. thiosulfuric thiothixene Related Content Daily Word Quiz: frugal Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language