/ Dictionary / Index A ammonium thiosulfate: Meaning and Definition of Find definitions for: ammo'nium thiosul'fate Pronunciation: [key] — Chem. Chem. a white, crystalline, water-soluble solid, (NH)SO, used chiefly in the manufacture of cleaning compounds for alloys having a tin or lead base. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. ammonium thiocyanate ammono Related Content Daily Word Quiz: deleterious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language