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I have been playing the piano for 8 years and today I was reading the Katchaturian Toccata and I discovered a symbol, which can be seen below. I am mystified and searched for “Music symbols” but didn’t discover my symbol on Wikipedia, neither on YouTube nor anywhere else. In search for the symbol I came across this post on the site What does a straight line followed by a sharp point mean in a piano score when under notes?, but it did not list it. I searched for an hour without result, so here I am writing this question.