Definition of: cylinder

(sil′in·dər) noun
1. Geom. a A solid described by the circumference of a circle as its center moves along a straight line: the ends of the solid are parallel, equal circles. It is called a right cylinder when the line along which the center moves is at right angles to the plane of the circle, and oblique cylinder when the line is not at right angles b Any curved surface generated by the motion of a straight line remaining parallel to itself and constantly intersecting a curve.
2. Any cylindrical portion of a machine, especially if hollow, and proportioned so that the length exceeds the diameter.
3. Mech. A cylindrical member of a motor in which a piston moves and receives direct impact from the steam or other motive fluid.
4. A rotating cylindrical portion of a printing press.
5. The rotating chamber that holds the cartridges of a revolver.
6. A cylindrical stone bearing an inscription; especially, an inscribed clay tablet, found buried under the corners of edifices in Babylonia and Assyria.
—v. t. To press or fit with a cylinder. [<L cylindrus <Gk. kylindros <kylindein roll]