##  [Thickening](/thickening) 

  ##  [Thickening](https://puremath.quantumdictionary.io/thickening-0) 

  

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- Mathematics & Logic -

**Pure Mathematics Dictionary**

 







 

 

 

 



 

 

 

 

Definition

The process or result of replacing a subspace A ⊂ M by a neighborhood N ⊂ M that is homeomorphic to a manifold-with-boundary and contains A as a deformation retract; often called a regular neighborhood in manifold and PL settings.