piston

noun pis·ton \ ˈpi-stən \
Updated on: 11 Sep 2017

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

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


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