parabola

[ puh-rab-uh-luh ]

noun

, Geometry.

1. 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: y 2 = 2 px or x 2 = 2 py.

parabola

/ pəˈræbələ /

noun

1. 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

parabola

/ pə-răb′ə-lə /

1. 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.

parabola

1. A geometrical shape ( see geometry ) consisting of a single bend and two lines going off to an infinite distance.

Notes

An object that is propelled away from the Earth and then drawn back by gravity , such as a fly ball in baseball, follows a path shaped like a parabola.

Word History and Origins

Origin of parabola¹

1570–80; < New Latin < Greek parabolḗ an application. See parable

Word History and Origins

Origin of parabola¹

C16: via New Latin from Greek parabolē a setting alongside; see parable

Example Sentences

The stone, with the rope trailing it, made a small parabola in the air, and the line, as if with a sigh, fell limply into the river only ninety tails away.

From Literature

The shortage of shells meant Danylo couldn’t fire his gun from a distance as he would an artillery piece, the round arcing in a parabola.

From Los Angeles Times

They interlock, forming a three-dimensional-looking beam comprised of geometric patterns — a rotated hyperbolic parabola .

From Los Angeles Times

Among his discoveries was a need to move his takeoff point farther back for higher jumps, so he could change the apex of the parabola shape of his jump to clear the bar.

From Seattle Times

Seen from the ground, their ephemeral parabolas look like calligraphic brushstrokes.

From Washington Post

Related Words

• arc
• arch
• contour
• loop
• trajectory