/ Dictionary / Index B base exchange: Meaning and Definition of Find definitions for: base' exchange" Pronunciation: [key] — U.S. Air Force. U.S. Air Force. a department store operated under government supervision at an air base. Abbr.: BX Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. base estate basehearted Related Content Daily Word Quiz: arboreal Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language