Meaning of “cylinder” - Learner’s Dictionary

cylinder

noun [ C ] uk us /ˈsɪlɪndər/
SHAPE

a shape with circular ends and long, straight sides, or a container or object shaped like this:

an oxygen cylinder
CAR PART

a part in a car or machine's engine that is shaped like a tube, and where another part moves up and down

(Definition of “cylinder” from the Cambridge Learner’s Dictionary © Cambridge University Press)