The crossword solution for the term FIRST OR SECOND is GEAR. GEAR is a mechanical device consisting of a toothed wheel or cogwheel that meshes with another toothed part in order to transmit torque. It is used to change the speed or direction of a machine, such as a motor vehicle, or to change the magnitude of a force. Gears are also used in many other applications, such as clocks, watches, and bicycles.