/ Dictionary / Index L linear equation: Meaning and Definition of Find definitions for: lin'ear equa'tion Pronunciation: [key] — Math. Math. a first-order equation involving two variables: its graph is a straight line in the Cartesian coordinate system. any equation such that the sum of two solutions is a solution, and a constant multiple of a solution is a solution. Cf. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. linear differential equation linear fractional transformation Related Content Daily Word Quiz: supercilious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language