Definition from Wiktionary, the free dictionary
Etymology 1 
Cardinal numeral 
cardinal number 86
Etymology 2 
- (colloquial) To cancel an order for food.
- "eighty-six the ham and eggs for table two!"
- (colloquial) To remove an item from the menu.
- eighty-six the lobster bisque - we won't have the lobster delivery until tomorrow.
- "Yes, I'd like the tomato soup." / "I'm sorry sir, that's been eighty-sixed - would you like a salad instead?"
- (colloquial) To remove or eject, as a disruptive customer
- Ryan and his friends got too rowdy at the bar, so they were eighty-sixed.
- (colloquial) To throw out; discard.
- "We finally had to eighty-six that old printer after it jammed one too many times."
- "Eighty-six" in Michael Quinion, Ballyhoo, Buckaroo, and Spuds, 2004.