/ Dictionary / Index G grade separation: Meaning and Definition of Find definitions for: grade' separa"tion Pronunciation: [key] separation of the levels at which roads, railroads, paths, etc., cross one another in order to prevent conflicting rows of traffic or the possibility of accidents. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. grade-schooler gradient Related Content Daily Word Quiz: neologism Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language