piston

noun
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

Piston

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 Korean automaker, under pressure from safety regulators, is recalling about 20,000 Veloster cars in the U.S. and Canada because fuel can prematurely ignite in the cylinders around the pistons. Tom Krisher, The Seattle Times, "Hyundai finds new engine problem, prompting another recall," 30 Mar. 2019 Instead of using shims or lubricants to decouple the pad from the caliper, stick the backing plate to the piston or caliper housing, effectively making its mass far larger. Mike Allen, Popular Mechanics, "How to Fix Squeaky Brakes," 14 Mar. 2019 Suddenly, its piston engine blew, throwing two connecting rods. Eric Tegler, Ars Technica, "One man designed and built the ultimate bush plane," 11 Aug. 2018 Like any piston engine, its power diminishes as altitude increases. Eric Tegler, Ars Technica, "One man designed and built the ultimate bush plane," 11 Aug. 2018 That ratio compares the maximum to minimum value of cylinder volume as the piston travels throughout its complete range. Matthew Jancer, Popular Mechanics, "How Infiniti's Variable-Compression Engine Works," 16 July 2018 Because the pistons are horizontally opposed, the boxer engine sits lower in the bay and has less vibration than inline or V-6 set ups. Robert Duffer, chicagotribune.com, "Review: Subaru climbs into 3-row class with 2019 Ascent," 26 June 2018 Atmospheric pressure then pushed the piston down and lifted the payload. Charles R. Morris, WSJ, "‘Energy’ Review: The Path to Power," 21 June 2018 By the very nature of its design, a rotary engine is lighter, less complex, and higher-revving than a typical box of pistons. Blake Z. Rong, Popular Mechanics, "​​The Evolution of the Combustion Engine​​," 5 June 2018

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

Noun

1704, in the meaning defined at sense 1

History and Etymology for piston

Noun

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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Statistics for piston

Last Updated

18 Apr 2019

Look-up Popularity

Time Traveler for piston

The first known use of piston was in 1704

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More Definitions for piston

piston

noun

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

piston

noun
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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