##  [Fold Singularity](/fold-singularity) 

  ##  [Fold Singularity](https://puremath.quantumdictionary.io/fold-singularity-0) 

  

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- Mathematics & Logic -

**Pure Mathematics Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A local corank-one singularity of a smooth map between manifolds in which the map, in suitable local coordinates, has the standard quadratic normal form in one transverse direction so that a hypersurface is mapped with a crease or fold; classically called the Whitney fold.