/ Dictionary / Index D dim-out: Meaning and Definition of Find definitions for: dim-out Pronunciation: (dim'out"), [key] — n. a reduction or concealment of night lighting in wartime to make the source less visible to an enemy from the air or sea. a reduction of night lighting caused by a failure in an electric generating system or a reduction in its output. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: dim-out (Thesaurus) dimorphous dimple Related Content Daily Word Quiz: reclusive Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language