Piston

/ˈpɪstən/

Meaning & Definition

noun
A cylindrical piece that moves back and forth within a cylinder, often used in engines or pumps to convert pressure into mechanical energy.
The engine's piston moved rapidly up and down, generating the power needed to drive the vehicle.
A device for drawing liquid from a container by means of suction.
She used a piston to transfer the liquid from the large tank into smaller bottles.
A part of a syringe that is pushed and pulled to create a vacuum or to inject fluids.
The nurse inserted the needle and slowly pulled back the piston to draw blood.
An object resembling a piston, often used in various machines.
The hydraulics of the machine were powered by a series of pistons that controlled the movement.
In musical instruments like a trumpet, a mechanism that changes the pitch by altering the length of the tubing.
The musician pressed down on the piston to lower the note during the performance.

Etymology

Middle English: from Old French pistoun, from Latin pistionem, meaning 'to crush'.

Common Phrases and Expressions

piston pump
A type of pump that uses a piston to move fluid.
piston ring
A ring used to seal the gap between the piston and the cylinder wall.
piston engine
An engine that uses pistons in its operation.

Related Words

cylinder
A three-dimensional shape with two parallel circular bases.
valve
A device that regulates the flow of a fluid in a pipe.

Slang Meanings

To piston down or up
We need to piston down these ideas to get to the point.
Piston head
He thinks he’s the piston head around here, but we all know the truth.