pl. -·las or -·lae·
Geom. the path of a point that moves so that the difference of its distances from two fixed points, the foci, is constant; curve formed by the section of a cone cut by a plane more steeply inclined than the side of the cone
Origin of hyperbolaModern Latin ; from Classical Greek hyperbol?, a throwing beyond, excess ; from hyperballein, to throw beyond ; from hyper- (see hyper-) + ballein, to throw (see ball)
nounpl. hy·per·bo·las or hy·per·bo·lae
A plane curve having two branches, formed by the intersection of a plane with both halves of a right circular cone at an angle parallel to the axis of the cone. It is the locus of points for which the difference of the distances from two given points is a constant.
Origin of hyperbolaNew Latin, from Greek huperbol&emacron;, a throwing beyond, excess (from the relationship between the line joining the vertices of a conic and the line through its focus and parallel to its directrix); see hyperbole.
The equation of this hyperbola is
x2 - y2 = 1.
(plural hyperbolas or hyperbolae or hyperbolæ)
From Ancient Greek ὑπερβολή (huperbolē).