/ Dictionary / Index L letdown: Meaning and Definition of Find definitions for: let•down Pronunciation: (let'doun"), [key] — n. a decrease in volume, force, energy, etc.: a letdown in sales; a general letdown of social barriers. disillusionment, discouragement, or disappointment: The job was a letdown. depression; deflation: He felt a terrible letdown at the end of the play. the accelerated movement of milk into the mammary glands of lactating mammals upon stimulation, as by massage or suckling. the descent of an aircraft from a higher to a lower altitude preparatory to making an approach and landing or to making a target run or the like. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: letdown (Thesaurus) letch Letha 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