pis·​ton | \ ˈpi-stən How to pronounce piston (audio) \

Definition of piston

 (Entry 1 of 2)

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


biographical name
Pis·​ton | \ ˈpi-stən How to pronounce Piston (audio) \

Definition of Piston (Entry 2 of 2)

Walter Hamor 1894–1976 American composer

Examples of piston in a Sentence

Recent Examples on the Web: Noun The braking distance from 70 mph, 170 feet, is six feet longer than that of a BMW X5 4.6is—this despite the fact the Cayenne has six-piston front calipers and gigantic vented discs. Dan Neil, Car and Driver, "Tested: 2003 Porsche Cayenne Turbo Takes Fast SUVs to New Heights," 2 June 2020 But in keeping with more than four decades of Technic car models, this one still has functional suspension, steering, moving pistons inside its engine, and a working eight-speed paddle-shift gearbox. Jonathan M. Gitlin, Ars Technica, "Lego brings out a $380, 3,969-piece Lamborghini Sián FKP 37 kit," 28 May 2020 In order to do that, check the number of steps the piston has: The more there are, the higher each stroke will lift the jack. Field & Stream, "Three Questions To Ask Before Buying A Hydraulic Jack," 12 May 2020 To handle the output and 8,250-rpm redline, the crankshaft, pistons and connecting rods are forged. Jeff Yip, Houston Chronicle, "Snakes alive! Shelby GT500 is the ultimate Mustang," 14 Apr. 2020 And experts say the parts at risk are likely greater than that, since many Chinese parts, from computer chips down to screws and bolts, are not classified simply as auto parts the way a bumper or engine piston is classified that way. Chris Isidore, CNN, "The coronavirus crisis could shut auto plants around the world," 9 Feb. 2020 Not only do its drivers get the go, the Shelby GT500 delivers the whoa via massive Brembo 16.5-inch front rotors and six-piston calipers. Jeff Yip, Houston Chronicle, "Snakes alive! Shelby GT500 is the ultimate Mustang," 14 Apr. 2020 The brakes, which include six-piston Brembos up front, have massive stopping power and pedal feedback that makes them easy to modulate. cleveland, "Cadillac CT5-V sport sedan arrives as 2020’s most pleasant surprise (review)," 4 Apr. 2020 Ray Stubblebine/Associated Press UNIONDALE, N.Y. — Now that John Tonelli’s return to the Nassau Coliseum ice is near, his emotions are churning like his old piston-driving skating style. Allan Kreda, New York Times, "John Tonelli and the Islanders Thaw the Ice After 34 Years," 20 Feb. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'piston.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of piston


1704, in the meaning defined at sense 1

History and Etymology for piston


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

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Time Traveler for piston

Time Traveler

The first known use of piston was in 1704

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Statistics for piston

Last Updated

18 Jun 2020

Cite this Entry

“Piston.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/piston. Accessed 2 Jul. 2020.

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More Definitions for piston


How to pronounce Piston (audio)

English Language Learners Definition of piston

: a part of an engine that moves up and down inside a tube and that causes other parts of the engine to move


pis·​ton | \ ˈpi-stən How to pronounce piston (audio) \

Kids Definition of piston

: 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

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More from Merriam-Webster on piston

Rhyming Dictionary: Words that rhyme with piston

Spanish Central: Translation of piston

Nglish: Translation of piston for Spanish Speakers

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