I have lots of friends who work in or have worked in the food-service industry to varying degrees. but none of them can tell me where the hell the term "86" comes from! 86 is what kitchen staff uses to inform the wait staff and others that they are out of an item- for example, "86 on tuna fish!", when its all gone. luckily, this answer was slightly easier to find then some in the past... but even that does not give one straight answer. sigh.
"According to Chef Dan Phillips, a restaurant history buff of sorts, the term "86" traces back to legendary French chef Georges-Auguste Escoffier, "the grandfather of cooking." Escoffier's career took him to the kitchens of the Moulin Rouge and London's Savoy Hotel in the late 1800's. Legend has it that Escoffier once could not complete a recipe that he had in mind because he could not find the 86th and final ingredient. A cold and rainy March Saturday led the Kona Breezeeditorial staff to a search for other explanations for the term, which they report as follows: At Delmonico's, America's first restaurant, the rib eye steak, Item 86, was out one night, thus the term. In the days of soup kitchens, they prepared enough soup for 85 people, so the 86th man in line was out of luck. 86 once meant "dead and buried," as in 8 feet long and 6 feet deep, the common specs for a grave for the averagesized man. In radio communication by telegraph key, the kind used at sea, 86 means "ignore previous message" or "eliminate." (More useful, by the way, is 88, "hugs and kisses.") Finally, we found that restaurants borrowed the term from bars, who "86ed" someone who had had too much to drink, a reference to Article 86 of the New York State Liquor Laws that limit service of alcoholic beverages."