Never heard that before. I think it is only used in Germany this way. As so many words. An Austrian would rather cut his tongue out than saying something like Quark for example.The Hochdeutsch expression is Geraffel.
See here: https://www.dict.cc/german-english/Geraffel.html
From there you can delve into the various dialects, where the first e is dropped and it's just pronounced G'raffel.
But the actual noun is still Geraffel.
We are teaching Graffel.
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