/ Dictionary / Index A ammonium bicarbonate: Meaning and Definition of Find definitions for: ammo'nium bicar'bonate Pronunciation: [key] — Chem. Chem. a white, crystalline, water-soluble solid, NHHCO, used chiefly in the manufacture of baking powder. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. ammonium alum ammonium bifluoride Related Content Daily Word Quiz: labyrinth Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language