/ Dictionary / Index M molybdenum trioxide: Meaning and Definition of Find definitions for: molyb'denum triox'ide Pronunciation: [key] a white, crystalline, sparingly water-soluble powder, MoO, used chiefly in the manufacture of molybdenum compounds. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. molybdenum disulfide molybdic Related Content Daily Word Quiz: soporific Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language