##  [Isothermal Compressibility](/isothermal-compressibility) 

  ##  [Isothermal Compressibility](https://engineering.quantumdictionary.io/isothermal-compressibility-0) 

  

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**Engineering & Applied Technologies Dictionary**

 







 

 

 

 



 

 

 

 

Definition

The isothermal compressibility Β_T of a material or fluid is the relative (fractional) change in volume per unit increase in pressure at constant temperature, defined by Β_T = -1/V (∂V/∂P)_T and equal to the reciprocal of the isothermal bulk modulus; it quantifies the volumetric susceptibility of a system to pressure changes under isothermal conditions for small perturbations around a given state.