- The definition of a quadratic equation is one in which one of the terms is raised to the second power (squared).
An example of a quadratic equation is 2x² + 4x + 4.
quadratic equation definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
Algebra an equation in which the second power, or square, is the highest to which the unknown quantity is raised
quadratic equation definition by American Heritage Dictionary
An equation in which one or more of the terms is squared but raised to no higher power, having the general form ax2 + bx + c = 0, where a, b, and c are constants.