##  [Prime End](/prime-end) 

  ##  [Prime End](https://puremath.quantumdictionary.io/prime-end-0) 

  

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- Mathematics & Logic -

**Pure Mathematics Dictionary**

 







 

 

 

 



 

 

 

 

Definition

An equivalence class of nested chains of crosscuts (or null-separating arcs) in a planar domain that formalizes a mode of approach to the domain's frontier; prime ends compactify the domain by adding boundary ideal points capturing boundary-accessibility and approach behavior.