Which term refers to the connecting end of a fastener or bolt that has spiral grooves cut into it?

The term that refers to the connecting end of a fastener or bolt that has spiral grooves cut into it is known as the threaded shank. The spiral grooves, or threads, are essential for the fastening mechanism. They allow the bolt or fastener to be screwed into a corresponding threaded hole or onto a nut, creating a secure connection. The design of the threaded shank enhances the mechanical grip and holding strength, making it a critical component in various construction and rigging applications. Understanding this terminology and its application is fundamental for anyone involved in rigging and related fields, as it aids in selecting the proper fasteners for specific tasks.