κύλινδρος

Greek kylindros (κύλινδρος) came from kylindein, 'to roll.' The word described any object that rolled — a log, a stone roller used for flattening ground, the cylinders used in printing and fabric production. The mathematical definition came later. Before it was a shape, a cylinder was an action: the act of rolling across a surface.

Greek mathematicians formalized the cylinder as a geometric solid. Archimedes, in the third century BCE, studied the cylinder intensively. His tomb, by his own request, was decorated with a cylinder enclosing a sphere — a reference to his proof that the surface area and volume of a sphere are two-thirds those of the circumscribing cylinder. This ratio was, in his view, his greatest achievement.

Latin borrowed cylindrus, and the word passed through French into English by the 1560s. In English, cylinder accumulated technical meanings: the chamber of a gun, the chamber of an engine, the drum of a printing press. All these cylinders share the Greek roller's essential quality — they are round, and things move through or around them.

The internal combustion engine made cylinder one of the most commonly used technical words of the twentieth century. A four-cylinder engine, a six-cylinder engine, an eight-cylinder engine — the Greek roller's descendants are under every hood. Archimedes proved theorems about cylinders. Henry Ford mass-produced them.