accelerator

Noun

• a scientific instrument that increases the kinetic energy of charged particles

• (chemistry) a substance that initiates or accelerates a chemical reaction without itself being affected

• a valve that regulates the supply of fuel to the engine

• a pedal that controls the throttle valve
  • he stepped on the gas
    

Related words

• Synonyms: 
  particle accelerator , atom smasher , catalyst , throttle , throttle valve , accelerator pedal , gas pedal , gas , gun