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A ball is a round object with various uses. It is used in ball games, where the play of the game follows the state of the ball as it is hit, kicked or thrown by players. Balls can also be used for simpler activities, such as catch or juggling. Balls made from hard-wearing materials are used in engineering applications to provide very low friction bearings, known as ball bearings. Black-powder weapons use stone and metal balls as projectiles.
Although many types of balls are today made from rubber, this form was unknown outside the Americas until after the voyages of Columbus. The Spanish were the first Europeans to see the bouncing rubber balls which were employed most notably in the Mesoamerican ballgame. Balls used in various sports in other parts of the world prior to Columbus were made from other materials such as animal bladders or skins, stuffed with various materials.
As balls are one of the most familiar spherical objects to humans, the word "ball" may be used to refer to or describe spherical or near-spherical objects.
"Ball" is used metaphorically sometimes to denote something spherical or spheroid, e.g., armadillos and human beings curl up into a ball, we make a ball with our fist.
The first known use of the word ball in English in the sense of a globular body that is played with was in 1205 in Laȝamon's Brut, or Chronicle of Britain in the phrase, "Summe heo driuen balles wide ȝeond Þa feldes." The word came from the Middle English bal from Proto-Germanic ballu-z , a cognate with Old High German ballo, pallo, Middle High German balle from Proto-Germanic *ballon , and Old High German ballâ, pallâ, Middle High German balle, Proto-Germanic *ballôn. No Old English representative of any of these is known. If ball- was native in Germanic, it may have been a cognate with the Latin foll-is in sense of a "thing blown up or inflated." In the later Middle English spelling balle the word coincided graphically with the French balle "ball" and "bale" which has hence been erroneously assumed to be its source. French balle is assumed to be of Germanic origin, itself, however. In Ancient Greek the word πάλλα for "ball" is attested besides the word "σφαίρα", sphere.