conchoid
[ kongkoid ]
/ ˈkɒŋ kɔɪd /

noun Geometry.
a plane curve such that if a straight line is drawn from a certain fixed point, called the pole of the curve, to the curve, the part of the line intersected between the curve and its asymptote is always equal to a fixed distance. Equation: r = b ± a sec(θ).
Nearby words
conchiolin, conchita, conchitis, concho, conchobar, conchoid, conchoidal, conchology, conchos, conchy, concierge
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Examples from the Web for conchoid
The conchoid has been employed by later mathematicians, notably Sir Isaac Newton, in the construction of various cubic curves.
Conchoid′al, pertaining to a conchoid: shelllike, applied to the fracture of a mineral; Concholog′ical, pertaining to conchology.
British Dictionary definitions for conchoid
conchoid
/ (ˈkɒŋkɔɪd) /
noun
geometry a plane curve consisting of two branches situated about a line to which they are asymptotic, so that a line from a fixed point (the pole) intersecting both branches is of constant length between asymptote and either branch. Equation: (x – a)²(x ² + y ²) = b ² x ² where a is the distance between the pole and a vertical asymptote and b is the length of the constant segment
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