/ Dictionary / Index B barium peroxide: Meaning and Definition of Find definitions for: bar'ium perox'ide Pronunciation: [key] — Chem. Chem. a grayish-white, water-insoluble, poisonous powder, BaO, used chiefly in the manufacture of hydrogen peroxide and as a bleaching agent for textiles. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. barium oxide barium stearate Related Content Daily Word Quiz: fidelity Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language