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—cylinderlike, adj./sil"in deuhr/, n.1. Geom. a surface or solid bounded by two parallel planes and generated by a straight line moving parallel to the given planes and tracing a curve bounded by the planes and lying in a plane perpendicular or oblique to the given planes.2. any cylinderlike object or part, whether solid or hollow.3. the rotating part of a revolver, containing the chambers for the cartridges.4. (in a pump) a cylindrical chamber in which a piston slides to move or compress a fluid.5. (in an engine) a cylindrical chamber in which the pressure of a gas or liquid moves a sliding piston.6. (in certain printing presses)a. a rotating cylinder that produces the impression and under which a flat form to be printed from passes.b. either of two cylinders, one carrying a curved form or plate to be printed from, that rotate against each other in opposite directions.7. (in certain locks) a cylindrical device for retaining the bolt until tumblers have been pushed out of its way.8. (in a screw or cylindrical gear) an imaginary cylindrical form, concentric to the axis, defining the pitch or the inner or outer ends of the threads or teeth.9. Computers. the tracks of a magnetic disk that are accessible from a single radial position of the access mechanism.10. Textiles. the main roller on a carding machine, esp. the roller covered with card clothing that works in combination with the worker and stripper rollers in carding fibers.11. Archaeol. a cylindrical or somewhat barrel-shaped stone or clay object bearing a cuneiform inscription or a carved design, worn by the Babylonians, Assyrians, and kindred peoples as a seal and amulet.v.t.12. to furnish with a cylinder or cylinders.13. to subject to the action of a cylinder or cylinders.[1560-70; < L cylindrus < Gk kýlindros roller, cylinder, akin to kylíndein to roll]
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in mechanical engineering, chamber of an engine in which a piston moves. See piston and cylinder.in geometry, surface of revolution that is traced by a straight line (the generatrix) that always moves parallel to itself or some fixed line or direction (the axis). The path, to be definite, is directed along a curve (the directrix), along which the line always glides. In a right circular cylinder, the directrix is a circle. The axis of this cylinder is a line through the centre of the circle, the line being perpendicular to the plane of the circle. In an oblique circular cylinder, the angle that the axis makes with the circle is other than 90°.The directrix of a cylinder need not be a circle, and if the cylinder is right, planes parallel to the plane of the directrix that intersect the cylinder produce intersections that take the shape of the directrix. For such a plane, if the directrix is an ellipse, the intersection is an ellipse.The generatrix of a cylinder is assumed to be infinite in length; the cylinder so generated, therefore, extends infinitely in both directions of its axis. A finite cylinder has a finite base, the surface enclosed by the directrix, and a finite length of generatrix, called an element.* * *
Universalium. 2010.