##  [BMO Space](/bmo-space) 

  ##  [BMO Space](https://puremath.quantumdictionary.io/bmo-space-0) 

  

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**Pure Mathematics Dictionary**

 







 

 

 

 



 

 

 

 

Definition

The space of locally integrable functions whose mean oscillation over balls (or cubes) is uniformly bounded; commonly denoted BMO and serving as a substitute for L^∞ in harmonic analysis, endpoint estimates, and commutator theory.