For random variables $A$ and $B$, $A \perp B$ is sometimes used to denote "A in independent of B". Is there a symbol that is commonly used to mean "A is not independent of B"?
From: Wasserman, L. (2013). All of Statistics: A Concise Course in Statistical Inference, Springer.
Wasserman uses a coil symbol. I have not found the Latex symbol, yet.
It seems that a crossed ⫫ would do it. In latex code \nBigCI or Unicode U+2aeb. Check its use at this nice lecture on causality https://www.youtube.com/watch?v=bHOGP5o3Vu0&t=2941s