Torus

Noun

1. The standard representation of such a space in 3-dimensional Euclidean space: a surface or solid formed by rotating a closed curve, especially a circle, about a line which lies in the same plane but does not intersect it (e.g. like a ring doughnut).

   "A 4-variable Karnaugh map can be thought of, topologically, as being a torus."

2. A topological space which is a product of two circles.

   "A 4-variable Karnaugh map can be thought of, topologically, as being a torus."

3. The product of the specified number of circles.
4. A ring-shaped object, especially a large ring-shaped chamber used in physical research.
5. A large convex molding, typically semicircular in cross section, which commonly projects at the base of a column and above the plinth.