- a pin or bolt, especially one on which something turns, as the gudgeon of a hinge.
- a pin, bolt, or hook by which a gun or the like is attached to the rear of a towing vehicle.
- a cast iron or steel base for a wooden post, often cast in a single piece with a cap for a lower post.
- a pin or bolt forming the pivot of a hinge
- the link bolt, hook, or pin on a vehicle's towing bracket
- the needle or plunger of the injection valve of an oil engine
