Craps is a game that involves rolling a pair of dice, and has given birth to a number of slang terms. The most commonly known term is snake eyes, and refers to the player rolling the dice with both dice showing a one. Since the roll is also known as the house edge, or the set statistical chance in which the house always wins, the two aces roll is highly negative, and hence was given the slang term of snake eyes. Snake eyes is the only bet in craps that is not included in other, broader betting options, and so must be bet on specifically in order to win.
Since that same bet also has a rather slim chance of winning, few make the bet. Hence, snake eyes is generally where the house will always make profit. In popular culture snake eyes is often used in ways not related to craps or dice games, since the term has become so infamous. It can be used to describe betrayal, sinister behaviour, an unscrupulous behaviour, and other such things.
Boxcars is a far less well known term, also originating from craps, and other casino games that use dice as the primary means of playing. The term refers to when both dice are showing sixes, since the multiple dots resemble the wheels of train boxcars.
Since the two sixes is included in broader betting options, it does not have as much an impact in the game of craps, and so does not have as much infamy attached. If wishing to bet on sixes, a player will often call out to the dealer the simple phrase boxcars, which indicates to the dealer that he is officially predicting the next roll will be two sixes. The term midnight is also used to indicate the same bet, since, of course, the two sixes add up to a total of twelve. The boxcars term is also used in other games that use dice.
Statistical Chances of Rolling Doubles
Gambling is a game based on odds and statistics, and dice games here mentioned are no different in this regard. A roulette wheel has thirty six number pockets, plus a single zero pocket in European roulette, or two zero pockets in the American version. It can then easily be worked out that predicting which specific pocket the ball will land in at any time is one in thirty seven.
A pair of dice on the other hand, has a one in thirty six chance of coming up as double ones, snake eyes, or double sixes, boxcars. This works out to a very slim two point eight percent probability that a person could ever accurately predict the numbers on both dice on any given roll. It is for this reason that such games provide wider betting options that lower the risk of a single bet, providing a more fair chance for the gambler to win at least some money. On a roulette wheel, the solution is to spread bets around the betting table, allowing some return to be made even if it is not the lucky umber bet.