piston
Definitions
General English
Aviation
- noun a solid cylinder that fits into a larger cylinder and moves under fluid pressure, as in petrol and diesel engines or compresses fluids, as in pumps and compressors
- noun a machine part that operates with a thrusting or plunging movement, e.g. a piston
Cars & Driving
- noun the reciprocating element in a reciprocating piston engine
- noun any immersing type of piston
- noun a hydraulic tappet component (e.g. in a valve)
- noun an actuating element in an ignition lock
- noun a piston in a starter solenoid
Construction
- A solid cylinder that fits inside a larger cylinder and moves as a result of the power it receives. It can be used to transmit power to or from a connecting rod. Found in reciprocating engines, pumps, and compressors.
Electronics
- In a waveguide, a sliding cylinder, usually consisting of a metal or dielectric, which is utilized for tuning. Also called plunger, waveguide plunger, or tuning piston.
- A cylinder or disk which is fitted closely within a larger cylinder, and which moves against the pressure of a fluid. An example is that in a dashpot.
- synonymplunger
Food
- barrel bread
Medical
- noun the part of a hypodermic syringe which slides up and down inside the tube, either sucking liquid into the syringe or forcing the contents out
Origin & History of “piston”
The Latin verb pinsere meant ‘beat, pound’. Its past participial stem pist- formed the basis for the noun pistillum ‘grinding stick, pestle’ (from which English gets pistil ‘female flower part’ (18th c.), an allusion to its shape). this passed into Italian as pestello, from which English gets pestle (14th c.). From the Italian stem pest- was formed pestone ‘rammer’, whose variant pistone gave French piston – whence English piston.
