Traditionally, to be eighty-sixed was to be cut off from further booze service. This term comes all the way from the wild
west (and not the 1980's as previously defined), where a bartender would only serve the
86 proof whiskey to customers already too drunk (
86 proof was reserved for the ladies. The wild
west was tough).
Today it means to be cut-off at the bar, kicked out of the bar, or to be cut-off or barred from something in general.