piston

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

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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

Tristan

Piston

biographical name Pis·ton \ˈpis-tən\

Definition of PISTON

Walter Hamor 1894–1976 Am. composer

PISTON Defined for Kids

piston

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