[kwo-drat-ik] /kwɒˈdræt ɪk/
1.
2.
Algebra. involving the square and no higher power of the unknown quantity; of the second degree.
noun
3.
1650-1660
Related forms
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Based on the Random House Dictionary, © Random House, Inc. 2016.
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/kwɒˈdrætɪk/
noun
1.
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
2.
of or relating to the second power
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
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Word Origin and History for quadratically

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
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 quadratic   (kwŏ-drāt'ĭk)    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
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