The swept volume in an engine is defined as:

The swept volume in an engine is accurately defined as the total volume the piston travels through during one stroke. This is a crucial aspect of an engine's design, as it represents the volume displaced by the piston as it moves from the top dead center (TDC) to the bottom dead center (BDC).

Understanding swept volume is essential because it directly relates to the engine's capacity and power output. The greater the swept volume, the more air-fuel mixture the engine can draw in during each intake cycle, which can translate into more power produced if the air-fuel mixture is efficiently processed.

Swept volume is distinct from other defined volumes in the engine, such as the combustion chamber volume, which is the space that remains when the piston is at TDC. While it's an important parameter for calculating compression ratios, it does not encompass the actual movement of the piston itself.

Thus, by recognizing the definition of swept volume as the total space the piston travels through during one stroke, it becomes clear how this measurement is integral to understanding engine performance and efficiency.