/ Dictionary / Index L lightfast: Meaning and Definition of Find definitions for: light•fast Pronunciation: (līt'fast", -fäst"), [key] — adj. not affected or faded by light, esp. sunlight; colorfast when exposed to light. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. lightface light-fingered 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