Definition:
A "piston rod" is a noun that refers to a connecting rod in a machine that connects a piston to a crank or wheel. It helps to transfer the movement created by the piston to other parts of the machine.
In more advanced discussions, you might talk about the materials used for piston rods (like steel or aluminum) or their role in different types of engines, such as internal combustion engines or hydraulic systems.
While there are no specific idioms or phrasal verbs directly related to "piston rod," you might come across phrases like "to get the gears turning," which metaphorically means to start a process or make something work, similar to how a piston rod helps machines operate.
In summary, a "piston rod" is an important component in various machines that helps translate the movement of a piston into useful work.