##  [Principal Point](/principal-point) 

  ##  [Principal Point](https://puremath.quantumdictionary.io/principal-point-0) 

  

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- Mathematics & Logic -

**Pure Mathematics Dictionary**

 







 

 

 

 



 

 

 

 

Definition

In the theory of prime ends for a domain D, a principal point is a boundary point x such that x is the unique element of the impression (limit set) of some prime end; equivalently, the impression of that prime end is the singleton {x}, so the prime end singles out x as its distinguished access point.