How did the phrase To 86 Someone become popular?

The phrase “to 86” generally means “put an end to”.

It is said to have been part of a number code used in diners and soda fountains.

In those early days, 86 meant “we’re out of that dish,” “don’t serve that customer,” or “don’t serve another drink to that customer because he’s already had too many.”

Over time, it has gained its more general meaning.