/ Dictionary / Index M Mercator projection: Meaning and Definition of Find definitions for: Merca'tor projec'tion Pronunciation: [key] a conformal projection on which any rhumb line is represented as a straight line, used chiefly in navigation, though the scale varies with latitude and areal size and the shapes of large areas are greatly distorted. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Mercator Mercator sailing Related Content Daily Word Quiz: vertigo Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language