Boxcars (slang)
Boxcars (also: "Midnight") is the outcome of rolling the dice in a game of craps and getting a 6 on each die. The pair of 6 pips resembles a pair of boxcars on a freight train. In modern parlance, it refers to such a roll in any game involving 6 sided dice which are marked with pips. The probability of this roll is 1 in 36, or about 2.8%. This is the same probability for throwing any set of pairs with the dice.
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