 ##  [Relative Permittivity](/index.php/relative-permittivity) 

  ##  [Relative Permittivity](https://engineering.quantumdictionary.io/relative-permittivity-0) 

  
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**Engineering &amp; Applied Technologies Dictionary**

 
Definition

The dimensionless ratio εr = ε/ε0 of a material's electric permittivity ε to the permittivity of free space ε0; it quantifies how an applied electric field is reduced inside the material relative to vacuum under specified frequency, temperature and field conditions.