cylinder
noun [ C ] uk/ˈsɪl.ɪn.dər/ us/ˈsɪl.ɪn.dɚ/
(SHAPE)
圆柱体;圆柱状物;圆筒（常用作容器）
a solid or hollow tube with long straight sides and two circular ends the same size, or an object shaped like this, often used as a container
Deep-sea divers carry cylinders of oxygen on their backs. 深海潜水员背上背有氧气筒。
(ENGINE PART)
（发动机的）汽缸
the tube-shaped device, found especially in an engine, inside which the part of the engine that causes the fuel to produce power moves up and down
a six-cylinder engine 六汽缸发动机