/ Dictionary / Index O outer: Meaning and Definition of Find definitions for: out•er Pronunciation: (ou'tur), [key] — adj. situated on or toward the outside; external; exterior: outer garments; an outer wall. situated farther out or farther from the center: the outer reaches of space. of or pertaining to the external world. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: outer (Thesaurus) outen outer automorphism Related Content Daily Word Quiz: perspicacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language