Wafer
This article is about wafers in semiconductor industry. See Wafer (cooking) for the original meaning of the word.
In microelectronics, a wafer is a thin slice of semiconducting material, such as a silicon crystal, upon which microcircuits are constructed by diffusion and deposition of various materials. Wafers are made in various sizes ranging from 1 inch (24.5 mm) to 12 inches (300 mm).
Note: Millions of individual circuit elements, constituting hundreds of microcircuits, may be constructed on a single wafer. The individual microcircuits are separated by scoring and breaking the wafer into individual chips ("dice").
Source: from Federal Standard 1037C