- a plane curve formed by the intersection of a right circular cone with a plane parallel to a generator of the cone; the set of points in a plane that are equidistant from a fixed line and a fixed point in the same plane or in a parallel plane. Equation: y2 = 2px or x2 = 2py.
Origin of parabola
Related Words for parabolatrajectory, arc, arch, contour, loop, swerve, sweep, hairpin, crook, bend, whorl, ambit, concavity, circle, quirk, curvature, festoon, bight, compass, circumference
Examples from the Web for parabola
Historical Examples of parabola
He reached the height of the 'parabola,' and is now about to descend.Debts of Honor
Is the orbit that of an ellipse, or a circle, or a parabola?Aether and Gravitation
William George Hooper
You will remember that a Republican State is represented by a parabola.The Romance of Mathematics
As a matter of fact the path of a projectile in vacuo is only approximately a parabola.
Its actual path will be a curve, which in this case is a parabola.
- a conic section formed by the intersection of a cone by a plane parallel to its side. Standard equation: y ² = 4 ax, where 2 a is the distance between focus and directrix
Word Origin for parabola
Word Origin and History for parabola
1570s, from Modern Latin parabola, from Greek parabole "parabola, comparison, analogy; application" (see parable), so called by Apollonius of Perga c.210 B.C.E. because it is produced by "application" of a given area to a given straight line. It had a different sense in Pythagorean geometry. Related: Parabolic.
- The curve formed by the set of points in a plane that are all equally distant from both a given line (called the directrix) and a given point (called the focus) that is not on the line.