cylinder

American  

[sil-in-der] / ˈsɪl ɪn dər /

noun

1. Geometry. 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)

   1. a rotating cylinder that produces the impression and under which a flat form to be printed from passes.

   2. 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, especially the roller covered with card clothing that works in combination with the worker and stripper rollers in carding fibers.

11. Archaeology. 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.

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verb (used with object)

1. to furnish with a cylinder or cylinders.

2. to subject to the action of a cylinder or cylinders.

cylinder British  

/ ˈsɪlɪndə /

noun

1. a solid consisting of two parallel planes bounded by identical closed curves, usually circles, that are interconnected at every point by a set of parallel lines, usually perpendicular to the planes. Volume base area × length

2. a surface formed by a line moving round a closed plane curve at a fixed angle to it

3. any object shaped like a cylinder

4. the chamber in a reciprocating internal-combustion engine, pump, or compressor within which the piston moves See also cylinder block

5. the rotating mechanism of a revolver, situated behind the barrel and containing cartridge chambers

6. printing any of the rotating drums on a printing press

7. Also called: cylinder seal.  a cylindrical seal of stone, clay, or precious stone decorated with linear designs, found in the Middle East and Balkans: dating from about 6000 _bc

8. Also called: hot-water cylinder.  a vertical cylindrical tank for storing hot water, esp an insulated one made of copper used in a domestic hot-water system

9. working or performing at full capability

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verb

1. (tr) to provide (a system) with cylinders

cylinder Scientific  

/ sĭl′ən-dər /

1. A three-dimensional surface or solid object bounded by a curved surface and two parallel circles of equal size at the ends. The curved surface is formed by all the line segments joining corresponding points of the two parallel circles.

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cylinder Idioms  

1. see firing on all cylinders.

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Other Word Forms

• cylinder-like adjective
• cylinderlike adjective

Etymology

Origin of cylinder

1560–70; < Latin cylindrus < Greek kýlindros roller, cylinder, akin to kylíndein to roll

Example Sentences

"I have been trying to book a gas cylinder for days now but I have had no luck so far. This has thrown all our plans in disarray," Prasad, 43, told AFP.

From Barron's • Mar. 20, 2026

Under the hood you’ll find a similarly storied power plant, Mazda’s Skyactiv-G 2.5-liter four cylinder gas engine.

From The Wall Street Journal • Feb. 27, 2026

Few breakfasts and refreshment breaks didn’t include someone squeezing a cylinder of icy concentrate into a pitcher, adding water and stirring until it became a drinkable delight.

From Salon • Feb. 6, 2026

The system consists of a box measuring about 1m x 1m x 0.4m which stands outside the property, as well as a heat pump unit and hot water cylinder inside the property.

From BBC • Jan. 27, 2026

As I shifted the cylinder back into place, another light appeared on the other side of the room.

From "The City Beautiful" by Aden Polydoros

Related Words

• barrel