In mathematics, a toroid is a doughnut-shaped object, such as an O-ring. It is a ring form of a solenoid. Its annular shape is generated by revolving a plane geometrical figure about an axis external to that figure which is parallel to the plane of the figure and does not intersect the figure. When a rectangle is rotated around an axis parallel to one of its edges, then a hollow cylinder (resembling a piece of straight pipe) is produced.
If the revolved figure is a circle, then the surface of such an object is known as a torus.
One of the best-known applications of the toroid shape is in a Tokamak device, which uses a magnetic field to confine a plasma in the shape of a torus.
- Stewart, B.; "Adventures Among the Toroids:A Study of Orientable Polyhedra with Regular Faces", 2nd Edition, Stewart (1964).
- The dictionary definition of toroid at Wiktionary
|This geometry-related article is a stub. You can help Wikipedia by expanding it.|