/ Dictionary / Index P plumbous oxide: Meaning and Definition of Find definitions for: plum'bous ox'ide Pronunciation: [key] — Chem. Chem. litharge. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. plumbous plumb rule Related Content Daily Word Quiz: fabricate Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language