accelerator Meaning, Definition & Usage

1. noun a pedal that controls the throttle valve
   gas pedal; throttle; accelerator pedal; gas; gun.
   
   • he stepped on the gas
2. noun a valve that regulates the supply of fuel to the engine
   throttle valve; throttle.
   
3. noun (chemistry) a substance that initiates or accelerates a chemical reaction without itself being affected
   catalyst.
   
4. noun a scientific instrument that increases the kinetic energy of charged particles
   atom smasher; particle accelerator.
   

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