[ kwo-drat-ik ]
/ kwɒˈdræt ɪk /


Algebra. involving the square and no higher power of the unknown quantity; of the second degree.


a quadratic polynomial or equation.

Nearby words

  1. quadrate muscle of loins,
  2. quadrate muscle of sole,
  3. quadrate muscle of thigh,
  4. quadrate muscle of upper lip,
  5. quadrate pronator muscle,
  6. quadratic equation,
  7. quadratic form,
  8. quadratic formula,
  9. quadratic residue,
  10. quadratics

Origin of quadratic

First recorded in 1650–60; quadrate + -ic

Related formsquad·rat·i·cal·ly, adverb

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for quadratic

British Dictionary definitions for quadratic


/ (kwɒˈdrætɪk) maths /


Also called: quadratic equation an equation containing one or more terms in which the variable is raised to the power of two, but no terms in which it is raised to a higher power


of or relating to the second power
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for quadratic



1650s, "square," with -ic + obsolete quadrate "a square; a group of four things" (late 14c.), from Latin quadratum, noun use of neuter adjective quadratus "square, squared," past participle of quadrare "to square, set in order, complete" (see quadrant). Quadratic equations (1660s) so called because they involve the square of x.

Online Etymology Dictionary, © 2010 Douglas Harper

Science definitions for quadratic


[ kwŏ-drătĭk ]

Relating to a mathematical expression containing a term of the second degree, such as x2 + 2.♦ A quadratic equation is an equation having the general form ax2 + bx + c = 0, where a, b, and c are constants.♦ The quadratic formula is x = -b ± √(b2 - 4ac)/2a. It is used in algebra to calculate the roots of quadratic equations.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.