/ Dictionary / Index E extragalactic: Meaning and Definition of Find definitions for: ex•tra•ga•lac•tic Pronunciation: (ek"stru-gu-lak'tik), [key] — adj. outside the Milky Way system. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: extragalactic (Thesaurus) extrafloral extragalactic nebula Related Content Daily Word Quiz: stringent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language