##  [Nonflatness](/nonflatness) 

  ##  [Nonflatness](https://algebra.quantumdictionary.io/nonflatness-0) 

  

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- Pure Mathematics -

**Algebra Dictionary**

 







 

 

 

 



 

 

 

 

Definition

The property of a module or morphism failing to be flat: tensoring with the module does not preserve exact sequences, so base change can produce nonexact results and torsion or Tor groups appear.