a pin joining the end of a connecting rod to a trunk piston or the end of a piston rod.
Origin
1870-75
Examples from the web for wrist pin
The connecting rod contains a machining defect in the wrist pin bushing of the rod that could cause a seizure of the piston pin.
The piston broke at the wrist pin hole and seized in the cylinder.
The piston is connected to the crank by a connecting rod and wrist pin.
British Dictionary definitions for wrist pin
wrist pin
noun
1.
a cylindrical boss or pin attached to the side of a wheel parallel with the axis, esp one forming a bearing for a crank
2.
(US & Canadian) the pin through the skirt of a piston in an internal-combustion engine, to which the little end of the connecting rod is attached Also called (esp in Britain) gudgeon pin