Was Trump threatened with death? What does "86" mean for Americans?

Zdjęcie: Liczba 86. Co oznacza w slangu? Źródło: Pexels


The number "86" is understood in the United States, for example, as a threat of death. On the another hand, it means, among another things, that a individual is not served in a peculiar location. Where did the word "86" come from and erstwhile did this "symbol" start to be used?