/ Dictionary / Index B base metal: Meaning and Definition of Find definitions for: base' met'al Pronunciation: [key] any metal other than a precious or noble metal, as copper, lead, zinc, or tin. Cf. noble metal, precious metal. the principal metal of an alloy. the principal metal of a piece underlying a coating of another metal; core. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. basement membrane Basenji Related Content Daily Word Quiz: paradox Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language