| Parabola 1. (n.) A kind of curve; one of the conic sections formed by the intersection of the surface of a cone with a plane parallel to one of its sides. It is a curve, any point of which is equally distant from a fixed point, called the focus, and a fixed straight line, called the directrix. See Focus. 2. (n.) One of a group of curves defined by the equation y = axn where n is a positive whole number or a positive fraction. For the cubical parabola n = 3; for the semicubical parabola n = /. Thesaurus Entries arc, bow, catacaustic, catenary, caustic, circle, conchoid, crook, curl, curve, diacaustic, ellipse, festoon, hook, hyperbola, lituus, sinus, tracery |