lemniscate

[ lem-nis-kit, lem-nis-keyt, -kit ]

noun

, Analytic Geometry.

1. a plane curve generated by the locus of the point at which a variable tangent to a rectangular hyperbola intersects a perpendicular from the center to the tangent. Equation: r 2 = 2 a 2 cosθ.

lemniscate

/ ˈlɛmnɪskɪt /

noun

1. a closed plane curve consisting of two symmetrical loops meeting at a node. Equation: ( x ² + y ²)² = a ²( x ² – y ²), where a is the greatest distance from the curve to the origin. The symbol for infinity (∞) is an example

Word History and Origins

Origin of lemniscate¹

First recorded in 1775–85, lemniscate is from the Latin word lēmniscātus adorned with ribbons. See lemniscus, -ate ¹