softball, variant of baseball played with a larger ball on a smaller field. Invented (1888) in Chicago as an indoor game, it was at various times called indoor baseball, mush ball, playground ball, kitten ball, and, because it was also played by women, ladies' baseball. The name softball was given to the game in 1926. A tournament (1933) at the Chicago World's Fair spurred interest in the game. The Amateur Softball Association of America (founded 1933) governs the game in the United States and sponsors annual sectional and world series championships. The International Softball Federation regulates rules of play in more than 110 countries, including the United States and Canada. Women's fast-pitch softball became an Olympic sport in 1996, but it (and baseball) were dropped beginning with the 2012 games.
Despite the name, the ball used is not soft. It is about 12 in. (30 cm) in circumference (sometimes larger for slow-pitch), which is 3 in. (8 cm) larger than a baseball. The infield in softball is smaller than in baseball; each base is 60 ft (18 m) from the next, as opposed to baseball's 90 ft (27 m). There are two types of softball: in the most common, slow-pitch softball, the ball, sometimes larger than the standard 12 in, must arch on its path to the batter, 10 players make up a team, and bunting and stealing are prohibited; in fast-pitch softball the pitch is fast, there are 9 players on a team, and bunting and stealing are permitted. Softball rules vary somewhat from those of baseball. Two major differences are that the ball must be pitched underhand—from 46 ft (14 m) for men or 40 ft (12 m) for women as compared with 60.5 ft (18.4 m) in baseball—and that seven innings instead of nine constitute a regulation game.
See M. Pagnoni and G. Robinson, Softball: Fast and Slow Pitch (1990).