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conic section

American  

noun

Geometry.
  1. a curve formed by the intersection of a plane with a right circular cone; an ellipse, a circle, a parabola, or a hyperbola.


conic section British  

noun

  1. Often shortened to: conic.  one of a group of curves formed by the intersection of a plane and a right circular cone. It is either a circle, ellipse, parabola, or hyperbola, depending on the eccentricity, e , which is constant for a particular curve e = 0 for a circle; e <1 for an ellipse; e = 1 for a parabola; e>1 for a hyperbola

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

conic section Scientific  
  1. A curve formed by the intersection of a plane with a cone. Conic sections can appear as circles, ellipses, hyperbolas, or parabolas, depending on the angle of the intersecting plane relative to the cone's base.


Etymology

Origin of conic section

First recorded in 1655–65