generally used in restaurant or food service environments when a specific item is no longer available. For example, "86 baked haddock", or "the mussels have been 86'ed", or in a bar when you may have drunk too much and can never come back.
used as a verb, to "eighty-six" means to "ignore" or "get rid of". The first recorded usage of this term occurs in the mid-1930s. Suggested theories of the origin of this usage include (in no particular order):
Eighty miles out and six feet under; when a person who is to be killed by the mafia is forced to dig his own grave many miles away from civilization.
Possibly a reference to article 86 of the New York state liquor code which defines the circumstances in which a bar patron should be refused service or "86ed".
Another theory has it that this is rhyming slang for "nix." However, if so, it would be a wholly American origin, and thus would be unusual for rhyming slang.[1]
Others have suggested that this usage originated from the famous Delmonico's Restaurant in New York City, as item number 86 on their menu, their house steak, often ran out during the 19th century. However, there is no recorded usage of this term in the nineteenth century.
Another explanation is that Chumley's, which was a famous 1900s New York speakeasy, is located at 86 Bedford St. During Prohibition, an entrance through an interior adjoining courtyard was used, as it provided privacy and discretion for customers. As was a New York tradition, the cops were on the payroll of the bar and would give a ring to the bar that they were coming for a raid. The bartender would then give the command "86 everybody!", which meant that everyone should hightail it out the 86 Bedford entrance because the cops were coming in through the courtyard door.
The term came into popular use among soldiers and veterans to describe missing soldiers as 86'd. Rather than describe buddies missing in action, it was slang to describe the MIA as being AWOL, therefore violating UCMJ Sub Chapter X Article 86.
Another explanation is the possibility of a simple variation of the slang term deep six, which has identical meaning, and is simply meant to describe the approximate depth of water needed for a burial at sea.
One possible origin is the public outdoor observatory on the 86th floor of the Empire State Building, the site of more than 30 suicides.
Another origin related to the Empire State Building is the fact that all the elevators stop at the 86th floor. Hence, everyone had to leave. The building opened in 1931, apparently a few years before the term became popular.
For many baseball fans, the most popular if misplaced reference was born of the 1986 playoff debacle for the Boston Red Sox. Game 6 and (eventually) the World Series slipped through the glove of first baseman Bill Buckner in the bottom of the 9th inning. The Sox didn't recover from the letdown in time for Game 7 and the New York Mets took the '86 crown. With Red Sox fans long considering the team to be cursed from trading Babe Ruth for cash and the 1986 World Series representing the closest shot the team had at winning the World Series in decades, the term '86 took on the meaning of "not happening."