a gear in a motor vehicle providing a gear ratio higher than that of direct drive (the usual top gear), so that the engine speed can be reduced at high road speeds to lessen fuel consumption or to allow further acceleration
a state of great or excessive activity
the city's worried public relations group went into overdrive
give (an electric guitar) a distorted sound
cranking the volume up results in overdriving the bass
drive or work to exhaustion
he says he did not overdrive the horses