The 2010 FIFA World Cup kicks off on Friday, with the United States slated to play England this weekend. For the 10th time since 1950, citizens of the two countries will square off over a game they call by different names. Given that so much of the world favors football, why do Americans call the game soccer?

It’s an abbreviation of association football. Both soccer and American football come from the same set of precursor sports, which became popular in upper-class English schools in the early 19th century and spread across the Atlantic. All these games involved advancing a ball through an opponent’s territory and scoring at the far end, but the rules varied from place to place. Ultimately, the version adopted as standard in the United Kingdom came to be known as association football, while another set of rules won out in the United States. Thus the Americans took to calling their gridiron variety football, and referred to the British sport by the slang term soccer, derived from the soc in association.

The history of football goes back hundreds of years, but the modern variety can be traced to the English boarding-school athletics craze. Every school played its own version of “football,” which led to confusion when players from one school met players from another. As the game spread, there were numerous attempts to devise a set of rules that everyone could follow. These tended to be hampered by acrimony between the schools and by anxiety about the fate of English masculinity. At least one impassioned advocate asserted that if English players were not allowed to hack one another in the shins, they might as well surrender to the French.

Finally, in October 1863, a group of representatives from 11 old boys’ clubs convened at the Freemasons’ Tavern in London to iron out a compromise. Calling themselves the Football Association, they held meetings for two months, then published The Book of Rules of Association Football, by a Group of Former English Public School Men. At the final meeting, however, the representative from Blackheath dramatically withdrew when the group voted to disallow shin-hacking and carrying the ball, longstanding traditions of the game as played at the Rugby School. Thus, at the moment when it was supposed to be unifying, English football split into two codes, association and rugby. Less official—or less English—versions of the game also continued to go their own way. Australian rules football, for instance, had been codified years before the Football Association first met; and Sheffield rules football, popular in England’s industrial north, wasn’t absorbed by the F.A. until 1877.

From this Victorian snarl, still more forms of football emerged. The gridiron style that now holds sway in America evolved in the later 19th century, from versions of rugby and association football that had been imported to the United States from Britain. For many years, the gridiron game was only one of many forms of football played in America.

Around the world, the F.A.’s version of the game continued to be called association football to distinguish it from the rest. In the 1880s, popular British slang took the soc from association and turned it into soccer. Throughout the first half of the 20th century, soccer, football, and soccer football were used more or less interchangeably throughout the English-speaking world. After a while, however, football began to prevail in countries where the F.A.’s rules were most popular, while soccer rose to the fore in countries (the United States, Canada, Australia) where a different version of the game predominated.

The current United States Soccer Federation was founded in 1913 as the United States of America Foot Ball Association. It was renamed the United States Soccer Football Association in 1945. The organization finally dropped the word football from its name in 1974.

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