A surface of revolution obtained by rotating a closed plane curve about an axis parallel to the plane which does not intersect the curve. The simplest toroid is the torus. The word is also used to refer to a toroidal polyhedron (Gardner 1975).
See alsoPappus's Centroid Theorem, Surface of Revolution, Tangent-Sphere Coordinates Toroidal Polyhedron, Torus
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ReferencesGardner, M. "Mathematical Games: On the Remarkable Császár Polyhedron and Its Applications in Problem Solving." Sci. Amer. 232, 102-107, May 1975.
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Cite this as:
Weisstein, Eric W. "Toroid." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/Toroid.html