a. and sb. Math. [f. L. quart-us fourth + -IC.] a. adj. Of the fourth degree. b. sb. A quantic, curve or surface of the fourth degree.
1856. Cayley, Wks. (1889), II. 263. We have for the quartic the following irreducible covariants, viz. the quartic itself U [etc.].
1885. Salmon, Mod. Higher Algebra, 345. Sylvester proved … that every invariant of a quartic is a rational function of S and T.
