/ Dictionary / Index B base bullion: Meaning and Definition of Find definitions for: base' bul'lion Pronunciation: [key] — Metall. Metall. smelted lead containing impurities, as gold, silver, or zinc, that are later removed. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. base box baseburner Related Content Daily Word Quiz: tenacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language