Cell walls in lath martensite - Meaning

What does cell walls mean in the context of lath martensite? Are they grain boundaries?


Quote (page 66 Structure and properties of engineering alloys - Smith): In the lath martensite of low-carbon steels, there is a high density of individual dislocations and many cell walls.


Sorry for the stupid question, I don't find any image to understand it.


Thank you for your time.




According to [this](https://en.wikipedia.org/wiki/Martensite) Wikipedia page: 



> 
> Martensite, named after the German metallurgist Adolf Martens
>  (1850–1914), most commonly refers to a very hard form of steel
>  crystalline structure, but it can also refer to any crystal structure
>  that is formed by diffusionless transformation.[1](https://en.wikipedia.org/wiki/Martensite) It includes a class
>  of hard minerals occurring as ***lath-*** [emphasis mine] or
>  plate-shaped crystal grains.
> 
> 
> 


Lath basically means the shape of a woven screen when viewed close up, or like a grid of alternating appearance.


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