decelerator

/diːˈsɛləreɪtər/
noun
  1. A device or mechanism that slows down the speed of a vehicle, machine, or process.
    • The factory installed a decelerator on the conveyor belt to prevent packages from crashing.
    • In some electric cars, the decelerator helps recharge the battery while braking.
    • The train's decelerator engaged smoothly as it approached the station.
Antonyms
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