Workpiece is the shop-floor term for the material or part being machined.
In Japanese shops it is shortened to "work."
The raw material about to be machined, the part in the middle of machining, and the finished product are all referred to as the "workpiece."
A Closer Look
On the shop floor it is an everyday word: "load the workpiece," "workpiece accuracy," "the workpiece is deflecting."
Drawings and specifications may instead use the term "work material" or "stock."
On a CNC automatic lathe, the workpiece is the small part being cut from bar stock.
The shape of the workpiece (slender or complex) and its material (easy or difficult to cut) determine the right machine, tools, and cutting conditions, so understanding the characteristics of the workpiece is the starting point of any machining job.