What does caliber in regards to a pocket watch mean?

In the context of pocket watches, "caliber" refers to the specific model or design of the watch movement, including its size, shape, and mechanical configuration. It denotes the internal components and the way they are arranged, which can affect the watch's accuracy, functionality, and overall quality. Different calibers can indicate varying features, such as complications, power reserve, and the number of jewels used in the movement. Each manufacturer often assigns a unique designation to their calibers for identification.