/ Dictionary / Index L lead dioxide: Meaning and Definition of Find definitions for: lead' diox'ide Pronunciation: (led), [key] — Chem. Chem. a brown crystalline compound, PbO, toxic, insoluble in water and alcohol, soluble in glacial acetic acid: used as an oxidizing agent, in lead-acid batteries, and in analytical chemistry. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. lead colic leaded Related Content Daily Word Quiz: dormant Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language