- The definition of a piston is a sliding valve that is snugly fitted into a cylinder in an engine and which moves up and down because of pressure, or a sliding valve in the cylinder of a brass instrument.
- An example of a piston is the part of a car that compresses fluids and creates fluid pressure.
- An example of a piston is the valve in a trumpet that changes the notes played by pushing down on one of three pistons.
piston definition by Webster's New World
- the snug-fitting engine part that is forced back and forth within a cylinder by the pressure of combustion, steam, etc. and a reciprocating connecting rod
- Music a sliding valve moved in the cylinder of a brass instrument to change the pitch
Origin: French ; from Italian pistone ; from pistare, to pound, crush ; from Late Latin frequentative of Classical Latin pinsere, to pound, beat: see pestle
piston definition by American Heritage Dictionary
- A solid cylinder or disk that fits snugly into a larger cylinder and moves under fluid pressure, as in a reciprocating engine, or displaces or compresses fluids, as in pumps and compressors.
- Music A valve mechanism in brass instruments for altering the pitch.
Origin: French, from Italian pistone, pestone, large pestle, from pestare, to pound, crush, from Late Latin pistāre, frequentative of Latin pīnsere, pīnsāre.
piston - Science Definition