##  [Optical Density](/optical-density) 

  ##  [Optical Density](https://natural.quantumdictionary.io/optical-density-0) 

  

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**Natural & Formal Sciences Dictionary**

 







 

 

 

 



 

 

 

 

Definition

Measure of light attenuation through a sample, typically reported as absorbance at a given wavelength or as a turbidity reading (for example OD600), used as a proxy for particle or cell concentration within an appropriate linear range.