# cissoid

[sis-oid]

- a curve having a cusp at the origin and a point of inflection at infinity. Equation: r = 2a sin(θ)tan(θ).

## Origin of cissoid^{}

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Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

# cissoid

- a geometric curve whose two branches meet in a cusp at the origin and are asymptotic to a line parallel to the y -axis. Its equation is y ²(2a – x) =x ³ where 2a is the distance between the y -axis and this line

- contained between the concave sides of two intersecting curvesCompare sistroid

## Word Origin

C17: from Greek kissoeidēs, literally: ivy-shaped, from kissos ivy

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
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