##  [Clopen Set](/clopen-set) 

  ##  [Clopen Set](https://puremath.quantumdictionary.io/clopen-set-0) 

  

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- Mathematics & Logic -

**Pure Mathematics Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A subset of a topological space that is both open and closed simultaneously; equivalently, a set whose complement is also open (hence closed) and which equals both its interior and its closure.