noun pis·ton \ˈpis-tən\

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

Full Definition of PISTON

:  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
:  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

Origin 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
First Known Use: 1704

Rhymes with PISTON


biographical name Pis·ton \ˈpis-tən\

Definition of PISTON

Walter Hamor 1894–1976 Am. composer
PISTON Defined for Kids


noun pis·ton \ˈpi-stən\

Definition of PISTON for Kids

:  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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