A baker\'s dozen, long dozen, long measure, or Roughrider\'s dozen is 13, one more than a standard dozen. The expression originated in 13th-century England.

The oldest known source, but questionable explanation for the expression \"baker\'s dozen\" dates to the 13th century in one of the earliest English statutes, instituted during the reign of Henry III (12161272), called the Assize of Bread and Ale. Bakers who were found to have shortchanged customers could be subject to severe punishment. To guard against the punishment of losing a hand to an axe, a baker would give 13 for the price of 12, to be certain of not being known as a cheat. Specifically, the practice of baking 13 items for an intended dozen was insurance against \"short measure\", on the basis that one of the 13 could be lost, eaten, burnt, or ruined in some way, leaving the baker with the original legal dozen. The practice can be seen in the guild codes of the Worshipful Company of Bak ...more