Source : Webster's Revised Unabridged Dictionary (1913)

Quartic \Quar"tic\, a. [L. quartus fourth.] (Mach.)
   Of the fourth degree.

Quartic \Quar"tic\, n.
   (a) (Alg.) A quantic of the fourth degree. See {Quantic}.
   (b) (Geom.) A curve or surface whose equation is of the
       fourth degree in the variables.

Source : WordNet®

quartic
     n : an algebraic equation of the fourth degree [syn: {biquadrate},
          {biquadratic}, {fourth power}]