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
His Pistons teams made nine straight playoff appearances, with five straight trips to the Eastern Conference finals, three straight NBA Finals appearances and two titles.
That piston is very strong and it cannot be removed.
A skull atop two crossed pistons is the insignia of the Outlaws.
The process operates a piston and drives the engine.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'piston'. Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
Definition of Piston
Walter Hamor 1894–1976 American composer
PISTON Defined for English Language Learners
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
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
Seen and Heard
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