piston

noun

pis·​ton ˈpi-stən 

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

Examples of piston in a Sentence

Recent Examples on the Web

There’s also a new lubrication system, forged pistons and rods, and revised exhaust manifolds that ensure durability in extended high-load, high-temperature environments. — Jerry Perez, The Drive, 3 Sep. 2026

Ford stated in its filing that in come cases a driver may experience a Check Engine Light, engine noise, or misfire as a warning that the engine piston dome may malfunction and cut power. — Jamie L. Lareau, Freep.com, 1 Sep. 2026

In the lab the frame was locked into an industrial rig where pneumatic pistons continuously hammer thousands of Newtons of force into the joints. — New Atlas, 29 Aug. 2026

More than 3,200 pistons distort two flexible mirrors with near atomic-scale precision to account for blemishes. — Noah Haggerty, Los Angeles Times, 28 Aug. 2026

Word History

Etymology

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, in the meaning defined at sense 1

Phrases Containing piston

• piston pin
• piston ring
• piston rod

Rhymes for piston

• cystine

Kids Definition

piston

noun

pis·​ton ˈpis-tən 

: a sliding piece moved by or moving against the pressure of a fluid (as steam or hot gases) that usually consists of a short solid cylinder moving within a larger hollow cylinder

Biographical Definition

Piston

biographical name

Pis·​ton ˈpi-stən 

Walter Hamor 1894–1976 American composer