What is the term used to describe the movement of the piston in the cylinder?

The term "stroke" specifically refers to the distance the piston travels within the cylinder during its complete motion, which includes both the upward and downward movements. In the context of an engine, each stroke corresponds to a specific phase of the engine's operation, such as the intake stroke, compression stroke, power stroke, and exhaust stroke. This terminology is crucial in understanding how the piston interacts with the combustion process and the engine's overall efficiency.

Other terms, while related to engine function, do not accurately define this specific action. "Cycle" refers to the complete sequence of events in engine operation (often comprising multiple strokes), "traverse" generally describes a movement back and forth without the specific implication of internal engine operation, and "movement" is a broad, non-specific term that could apply to various motions. Thus, "stroke" is the most precise term for the piston's movement within the cylinder.