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piston

noun pis·ton \ ˈpi-stən \
|Updated on: 13 Jun 2018

Definition of piston

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

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Recent Examples of piston from the Web

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Origin and Etymology of 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

Piston

biographical name Pis·ton \ ˈpi-stən \

Definition of Piston

Walter Hamor 1894–1976 American composer

PISTON Defined for English Language Learners

piston

noun

Definition of piston for English Language Learners

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

PISTON Defined for Kids

piston

noun pis·ton \ ˈpi-stən \

Definition of piston for Students

: 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

Learn More about piston

  1. See words that rhyme with piston Spanish Central: Translation of piston Nglish: Translation of piston for Spanish speakers

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