/ Dictionary / Index S string theory: Meaning and Definition of Find definitions for: string' the"ory Pronunciation: [key] — Physics. Physics. See under(def. 3). Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. string quartet string tie Related Content Daily Word Quiz: paradox Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language