fast (able to move quickly; able to do something quickly): She is a fast swimmer. I love fast cars.
quick (fast): Mike is a quick worker. He walks with quick steps.
speedy (quick, fast): Traveling by air is speedy and comfortable.
high-speed (moving or operating very quickly): The company provides high-speed Internet service.
express (traveling or operating at high speed): We took an express train to Tokyo. I’ll send the letter by express mail.
brisk (moving quickly, usually on foot): My doctor advised me to take a brisk walk every day.
supersonic (faster than the speed of sound): Supersonic jets can travel faster than the speed of sound.
