What defines a through hole in a workpiece?

A through hole in a workpiece is defined as a hole that extends from one surface of the material to the opposite surface. This means that the hole fully penetrates the material, providing a direct path from one side to the other, which is crucial for various applications such as fastening, fluid flow, or electrical connectivity.

The other definitions do not fit this description. A hole that is only slightly drilled into a surface does not extend completely through, making it a blind hole or simply a shallow hole in the material. A blind ending indicates that a hole does not pass all the way through the material, which is the opposite of a through hole. Lastly, a hole that is surrounded by threads refers to a threaded hole, which is specifically designed for the insertion of screws or bolts, adding another layer of functionality that does not pertain to the concept of a through hole itself. Thus, the correct choice accurately captures the essential feature of a through hole.