Cissoid
Given two curves 
and 
and a fixed point 
, let a line from cut at 
and at 
. Then theLocus of a point 
such that 
is the cissoid. The word cissoid means ``ivy shaped.''
| Curve 1 | Curve 2 | Pole | Cissoid |
| Line | Parallel Line | any point | line |
| Line | Circle | center | Conchoid of Nicomedes |
| Circle | tangent line | on Circumference | oblique cissoid |
| Circle | tangent line | on Circumference opp. tangent | Cissoid of Diocles |
| Circle | radial line | on Circumference | strophoid |
| Circle | concentric Circle | center | Circle |
| Circle | same Circle |  | Lemniscate |
References
Lawrence, J. D. A Catalog of Special Plane Curves. New York: Dover, pp. 53-56 and 205, 1972. Lee, X. ``Cissoid.''http://www.best.com/~xah/SpecialPlaneCurves_dir/Cissoid_dir/cissoid.html. Lockwood, E. H. ``Cissoids.'' Ch. 15 in A Book of Curves. Cambridge, England: Cambridge University Press, pp. 130-133, 1967. Yates, R. C. ``Cissoid.'' A Handbook on Curves and Their Properties. Ann Arbor, MI: J. W. Edwards, pp. 26-30, 1952.
- D-Number
- Dobinski's Formula
- Dodecadodecahedron
- Dodecagon
- Dodecagram
- Dodecahedral Conjecture
- Dodecahedral Graph
- Dodecahedral Space
- Dodecahedron
- Dodecahedron 2-Compound
- Dodecahedron-Icosahedron Compound
- Dodecahedron Stellations
- Domain
- Domain Invariance Theorem
- Dome
- Dominance
- Domino
- Domino Problem
- Donaldson Invariants
- Donkin's Theorem
- Donut
- Doob's Theorem
- Dot
- Dot Product
- Variate