quadratic

adj. containing terms raised to no higher than the second degree (Algebra)

n. equation containing terms raised to no higher than the second degree (Algebra)

In mathematics, the term quadratic describes something that pertains to squares, to the operation of squaring, to terms of the second degree, or equations or formulas that involve such terms. Quadratus is Latin for square.
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Noun
1. an equation in which the highest power of an unknown quantity is a square
(synonym) quadratic equation
(hypernym) equation
2. a polynomial of the second degree
(synonym) quadratic polynomial
(hypernym) polynomial, multinomial
Adjective
1. of or relating to or resembling a square; "quadratic shapes"
(pertainym) square, foursquare
2. of or relating to the second power; "quadratic equation"
(pertainym) square, second power

(a.)
Tetragonal.
  

(a.)
Pertaining to terms of the second degree; as, a quadratic equation, in which the highest power of the unknown quantity is a square.
  

(a.)
Of or pertaining to a square, or to squares; resembling a quadrate, or square; square.
  

Fits a second-order polynomial function to the points in the 3D scatterplot.