/ Dictionary / Index M mdse.: Meaning and Definition of Find definitions for: mdse. Pronunciation: [key] merchandise. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. MDR MDT Related Content Daily Word Quiz: tactful Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language