piston
noun
pis·ton ˈpi-stən 
1
: a sliding piece moved by or moving against fluid pressure which usually consists of a short cylindrical body fitting within a cylindrical chamber or vessel along which it moves back and forth
2
: a sliding valve moving in a cylinder in a brass instrument which when depressed by a finger knob serves to lower the instrument's pitch
Example Sentences
Recent Examples on the Web In Furioso, acceleration is ruthless, relentless, but with none of the sound and fury of a piston engine screaming its guts out, which makes the view out the windshield all the more intense and otherworldly. 
Mark Ewing, Forbes, 14 Aug. 2022 The panel also heard from Chris D’Acosta, the CEO of Swift Fuels, which sells unleaded aviation gas for planes that are compatible with it and hopes to have a formula ready for the full US fleet of piston-engine aircraft within the next three years. Heather Landy, Quartz, 1 Aug. 2022 After some initial resistance, the flight schools and operators at Reid-Hillview switched entirely to the new fuel, a lower-octane variety suitable for most piston engines. Michael J. Coren, Quartz, 16 June 2022 Placing the thick rubber hose on the arms of the piston like a sleeve prevents the doors from opening. Erik S. Hanley, Journal Sentinel, 4 Aug. 2022 The team created a pitching machine that looks like a massive nail gun, featuring a four-foot-long piston to drive the ball and accelerate it to speeds of up to 400 miles per hour. Tim Newcomb, Popular Mechanics, 12 Apr. 2022 The average piston-engine aircraft in the US is around 50 years old; very few are retired each year. Michael J. Coren, Quartz, 16 June 2022 The car is also fitted with six-piston Brembo brakes that provide stopping power and adaptive air suspension for a smoother ride. Rachel Cormack, Robb Report, 11 May 2022 Dual piston hydraulic disc brakes stop on a dime, even downhill. Lauren Mowery, Forbes, 1 June 2022 See More
Mark Ewing, Forbes, 14 Aug. 2022 The panel also heard from Chris D’Acosta, the CEO of Swift Fuels, which sells unleaded aviation gas for planes that are compatible with it and hopes to have a formula ready for the full US fleet of piston-engine aircraft within the next three years. Heather Landy, Quartz, 1 Aug. 2022 After some initial resistance, the flight schools and operators at Reid-Hillview switched entirely to the new fuel, a lower-octane variety suitable for most piston engines. Michael J. Coren, Quartz, 16 June 2022 Placing the thick rubber hose on the arms of the piston like a sleeve prevents the doors from opening. Erik S. Hanley, Journal Sentinel, 4 Aug. 2022 The team created a pitching machine that looks like a massive nail gun, featuring a four-foot-long piston to drive the ball and accelerate it to speeds of up to 400 miles per hour. Tim Newcomb, Popular Mechanics, 12 Apr. 2022 The average piston-engine aircraft in the US is around 50 years old; very few are retired each year. Michael J. Coren, Quartz, 16 June 2022 The car is also fitted with six-piston Brembo brakes that provide stopping power and adaptive air suspension for a smoother ride. Rachel Cormack, Robb Report, 11 May 2022 Dual piston hydraulic disc brakes stop on a dime, even downhill. Lauren Mowery, Forbes, 1 June 2022 See More Word History
Etymology
French, from Italian pistone, from pistare to pound, from Old Italian, from Medieval Latin, from Latin pistus, past participle of pinsere to crush — more at pestle
First Known Use
1704, in the meaning defined at sense 1
Phrases Containing piston
Kids Definition
piston
noun
pis·ton ˈpi-stən
: a disk or short cylinder that slides back and forth inside a larger cylinder and is moved by steam in steam engines and by the explosion of fuel in automobiles
Biographical Definition
Piston
biographical name
Pis·ton ˈpi-stən
Walter Hamor 1894–1976 American composer