##  [Inradius](/inradius) 

  ##  [Inradius](https://puremath.quantumdictionary.io/inradius-0) 

  

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- Mathematics & Logic -

**Pure Mathematics Dictionary**

 







 

 

 

 



 

 

 

 

Definition

The radius of the largest circle (in the plane) or sphere (in space) that can be inscribed in a polygon or polyhedron so that it is tangent to every side (edge) or face; for a triangle it is the radius of the incircle.