"86'd" means, variously, to get cut off from the booze at a bar or to get thrown out of a commercial establishment. In gambling lingo, it means that a player is barred from entering that casino ever again; if he does, he risks being arrested and charged with trespassing (it's also known as being read the Trespass Act).
According to Ian Andersen, the international high-stakes blackjack-playing health nut and Renaissance man, in his Huntington Press book Burning the Tables in Las Vegas -- Keys to Success in Blackjack and in Life, the term originated in the saloons of the American frontier West.
"The good saloons served 100-proof whiskey. However, ladies were served 86 proof. If a male customer began to get drunk and rowdy, the bartender would break out the bottle of 86 proof in front of all his friends. Embarrassed at having been served a 'lady's drink,' the macho cowboy would leave -- hence the term 86'd."
