# conchoid

[kong-koid] /ˈkɒŋ kɔɪd/
noun, Geometry.
1.
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).
Origin of conchoid
1790-1800
1790-1800; < Greek konchoeidḗs. See conch, -oid
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Based on the Random House Dictionary, © Random House, Inc. 2016.
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Examples from the Web for conchoid
Historical Examples
• conchoid′al, pertaining to a conchoid: shell-like, applied to the fracture of a mineral; Concholog′ical, pertaining to conchology.

• The conchoid has been employed by later mathematicians, notably Sir Isaac Newton, in the construction of various cubic curves.

British Dictionary definitions for conchoid

## conchoid

/ˈkɒŋkɔɪd/
noun
1.
(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(x² + y²) = b²x² where a is the distance between the pole and a vertical asymptote and b is the length of the constant segment
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
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### Word Value for conchoid

16
18
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