throttle

a valve that regulates the supply of fuel to the engine

a pedal that controls the throttle valve; "he stepped on the gas"

place limits on (extent or access); "restrict the use of this parking lot"; "limit the time you can spend with your friends"

kill by squeezing the throat of so as to cut off the air; "he tried to strangle his opponent"; "A man in Boston has been strangling several dozen prostitutes"

reduce the air supply; "choke a carburetor"