/ Dictionary / Index S superstring: Meaning and Definition of Find definitions for: su•per•string Pronunciation: (s'pur-string"), [key] — n. Physics. an elementary particle treated as a string in any string theory of supersymmetry. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: superstring (Thesaurus) superstratum superstring theory Related Content Daily Word Quiz: neologism Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language