/ Dictionary / Index L lackluster: Meaning and Definition of Find definitions for: lack•lus•ter Pronunciation: (lak'lus"tur), [key] — adj. lacking brilliance or radiance; dull: lackluster eyes. lacking liveliness, vitality, spirit, or enthusiasm: a lackluster performance. —n. a lack of brilliance or vitality. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: lackluster (Thesaurus) Lackland Air Force Base Laclos Related Content Daily Word Quiz: rustic Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language