/ Dictionary / Index S space mark: Meaning and Definition of Find definitions for: space' mark" Pronunciation: [key] — Print. Print. a proofreader's symbol used to indicate the need to insert space, as between two typed or printed words that have been run together. Symbol: # Cf.(def. 2). Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. space man space medicine Related Content Daily Word Quiz: fidelity Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language