/ Dictionary / Index L light therapy: Meaning and Definition of Find definitions for: light' ther"apy Pronunciation: [key] — Med. Med. therapeutic exposure to full-spectrum artificial light that simulates sunlight, used to treat various conditions, as seasonal affective disorder. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. light table lighttight Related Content Daily Word Quiz: jaundice Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language