conic section


: a plane curve, line, pair of intersecting lines, or point that is the intersection of or bounds the intersection of a plane and a cone with two nappes
: a curve generated by a point which always moves so that the ratio of its distance from a fixed point to its distance from a fixed line is constant

Illustration of conic section

Illustration of conic section
  • 1 straight lines
  • 2 circle
  • 3 ellipse
  • 4 parabola
  • 5 hyperbola

Examples of conic section in a Sentence

Recent Examples on the Web Given one rational point P on such a graph, there is an elegant way to find all the other rational points: Simply take each line that passes through P with a rational slope, and calculate the line’s second intersection point with the conic section. Quanta Magazine, 9 July 2013 The graphs of such curves are the conic sections — circles, parabolas, ellipses and hyperbolas. Quanta Magazine, 9 July 2013

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'conic section.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1664, in the meaning defined at sense 1

Time Traveler
The first known use of conic section was in 1664

Dictionary Entries Near conic section

Cite this Entry

“Conic section.” Dictionary, Merriam-Webster, Accessed 20 Jul. 2024.

Kids Definition

conic section

: a curve formed by the intersection of a plane and a cone

More from Merriam-Webster on conic section

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