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

Aircraft manufacturer Cirrus is launching a new safety system in a single-engine piston airplane. —Morgan Severson, CNN Money, 6 May 2025

Its distinguishing feature is the use of a jet engine, unlike other loitering munitions of similar size, which typically rely on piston engines. —Vikram Mittal, Forbes.com, 29 Apr. 2025

Bugatti/Jacob & Co. Where the Tourbillon V16 engine screams at 9,000 rpm, the Jacob and Co. miniature V16 purrs the seconds away with 16 tiny titanium pistons firing up and down inside a clear sapphire engine block. —New Atlas, 28 Apr. 2025

Traditionally, wall beds featured wood frames and pistons, while Murphy beds often used metal frames and springs. —Blake Bakkila, Architectural Digest, 17 Apr. 2025

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

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