##  [Closed Set](/closed-set) 

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

  

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- Mathematics & Logic -

**Pure Mathematics Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A subset C of a topological space (X, τ) whose complement X \ C is an open set; equivalently, a set that contains all its limit points or that equals its closure.