/ Dictionary / Index A attaché case: Meaning and Definition of Find definitions for: attaché' case" Pronunciation: [key] a flat, usually rigid, rectangular briefcase for carrying business papers, documents, or the like. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. attaché attached Related Content Daily Word Quiz: eureka Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language