a valve that regulates the supply of fuel to the engine
"The mechanic adjusted the throttle to ensure the carburetor was getting just the right amount of fuel for the engine to run smoothly."
a pedal that controls the throttle valve
"he stepped on the gas"
A valve that regulates the supply of fuel-air mixture to an internal combustion engine and thus controls its speed; a similar valve that controls the air supply to an engine.
"The mechanic adjusted the carburetor's throttle to ensure the car idled smoothly after the tune-up."
kill by squeezing the throat of so as to cut off the air
"he tried to strangulate his opponent"
"A man in Boston has been strangling several dozen prostitutes"
To cut back on the speed of (an engine, person, organization, network connection, etc.).
"The driver had to quickly throttle back the car's speed as a police cruiser flashed its lights behind him."
Throttle comes from the Middle English word throtel, which is a diminutive form meaning "little throat." It originally referred to something small or narrow related to the throat, similar to the German word for throttle.