/ Dictionary / Index S superagency: Meaning and Definition of Find definitions for: su•per•a•gen•cy Pronunciation: (s'pur-ā"jun-sē), [key] — pl. -cies. a very large agency, esp. a large government agency that oversees smaller ones. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. superaerodynamics superalloy Related Content Daily Word Quiz: soporific Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language