/ Dictionary / Index S surface density: Meaning and Definition of Find definitions for: sur'face den'sity Pronunciation: [key] — Physics. Physics. quantity, as of electric charge, per unit surface area. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. surface condenser surface effect ship Related Content Daily Word Quiz: procrastinate Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language