The radius used in performing an inversion with respect to an inversion circle.
Inversion Radius
See also
Circle Power, Inverse Points, Inversion Center, Inversion Circle, Inversion Pole, Inversive Distance, PolarExplore with Wolfram|Alpha
Cite this as:
Weisstein, Eric W. "Inversion Radius." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/InversionRadius.html