/ Dictionary / Index P plumbum: Meaning and Definition of Find definitions for: plum•bum Pronunciation: (plum'bum), [key] — n. Chem. lead. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. plumb rule plumcot 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