toroidal coordinate system

toroidal coordinate system

[tə¦rȯid·əl kō′ȯrd·ən·ət ‚sis·təm]
(mathematics)
A three-dimensional coordinate system whose coordinate surfaces are the toruses and spheres generated by rotating the families of circles defining a two-dimensional bipolar coordinate system about the perpendicular bisector of the line joining the common points of intersection of one of the families, together with the planes passing through the axis of rotation.