In a piston engine, a piston rod joins a piston to a connecting rod.
Many internal combustion engines, and in particular all current automobile engines, do not have true piston rods, and the term piston rod is often used as a synonym for connecting rod in the context of these engines.
All engines with crossheads do have true piston rods. These include most steam locomotives and large marine diesel engines.
Famous quotes containing the word rod:
“Yea, though I walk through the valley of the shadow of death, I will fear no evil: for thou art with me; thy rod and thy staff they comfort me.”
—Bible: Hebrew Psalms, 23:4.