DriverSide's Car Dictionary has the most comprehensive definitions of automotive terms. This auto glossary can help you decipher what your mechanic is fixing and what the purpose or function of the particular auto part or accessory is for. We have taken the mystery out of automotive service jargon, so that you don't have to.
This is often referred to by manufacturers, especially in regards to warranty coverage. Though definitions can vary, it mainly refers to primary engine and transmission components that make the car "go."