Where does the term "86" come from?

March 9, 1984

Dear Cecil:
A bunch of us were wondering where the term "86'd" comes from. We know about "can it" and "deep six" ... but what about "86"?
— Scott K., Los Angeles

Cecil replies:
Cecil presumes you are using the term "86" to mean "to put the kibosh on," generally said of some unusually retarded scheme or idea, such as anything thought up by the sales department, the New York office, or that turkey who's angling for your job.

The term derives via a roundabout route from a number code allegedly in wide use in 1920s diners and soda fountains. 86 supposedly meant, "We're all out of the item ordered," said by the cook or some other honcho to a soda jerk or similar minion.

Why 86 and not, say, the square root of 2? The most plausible explanation I've heard is that 86 is rhyming slang for "nix."

By extension 86 came to mean, "Don't serve anything to the indicated party because he is either broke or a creep." (Presumably you see how a code would come in handy in such situations.)

Bartenders later used the term in connection with any person deemed too hammered to serve additional drinks to, and eventually it came to have the all-purpose meaning we assign to it today.

Other lunch counter code numbers (I rely here on the Morris Dictionary of Word and Phrase Origins) include 82, I need a glass of water (80 and 81 at times meant the same thing); 99, the manager is on the prowl; 98, ditto for the assistant manager; 33, gimme a cherry-flavored Coke; 55, I crave a root beer; 19, I yearn for a banana split; and 87-1/2, check out the babe over yonder.

I know, so uncouth. But probably better than the term favored by high school guys in my day, namely "sluts on the right."

— Cecil Adams

From: www.straightdope.com