Which term describes the electrical/mechanical switching device used in the ignition system?

The term that describes the electrical/mechanical switching device used in the ignition system is the distributor. The distributor plays a crucial role in directing the high-voltage output from the ignition coil to the correct cylinder at the appropriate time during the engine's cycle. It does this by using a rotating arm that connects to individual spark plug wires, ensuring that each cylinder receives its spark at the correct moment for combustion.

In older ignition systems, the distributor works in conjunction with other components such as the ignition coil, breaker points, and sometimes a condenser. Although these components are part of the system, they each serve distinct purposes; for example, breaker points are used to open and close the circuit to generate a spark, while a condenser helps to prevent arcing at the points. The relay is typically used in electrical systems to control circuits but is not primarily a switching device for igniting fuel in the combustion process. Thus, the distributor stands out as the key component for coordinating the ignition timing in the engine.