9. A piece of mechanism for retarding or stopping motion by friction, as of a carriage or railway car, by the pressure of rubbers against the wheels, or of clogs or ratchets against the track or roadway, or of a pivoted lever against a wheel or drum in a machine.
10. (Engin.) An apparatus for testing the power of a steam engine, or other motor, by weighing the amount of friction that the motor will overcome; a friction brake.