The American Heritage® Dictionary of the English Language, 4th Edition
noun-plural. A game played on a large, netless, four-walled court by two or four players with long-handled rackets and a hard, fast-moving ball 1 inch (2.5 centimeters) in diameter.
n. a game for two or four players, played in an enclosed court with a small hard fast-moving ball
Word Usage
"James P. Conover, the St. Paul's master who also introduced ice hockey to the United States, had ordered rackets and balls from England for his new racquets courts (racquets is an older, faster, deadlier version of squash)."