As used in this article, the following terms shall have the meanings indicated:
Any mechanical, electromechanical, or electronic-mechanical device, or any combination thereof (also commonly called an "engine brake"), used for the purpose of supplementing the braking system of a diesel, gasoline, or propane powered motor vehicle engine.
That road designated by the Commonwealth of Pennsylvania as State Route 41 which, within the municipal limits of Avondale Borough, is called "Pennsylvania Avenue."