Which term refers to a guide or reference for symbols in commercial prints?

The term that refers to a guide or reference for symbols in commercial prints is "Legend." In the context of blueprints and technical drawings, a legend provides essential information by explaining the symbols, lines, and notations used in the drawing. It serves as an important tool for interpreting the information presented, ensuring that users can accurately understand what is depicted in the prints.

A legend typically includes clear descriptions that correspond to various graphical representations, making it easier for technicians, engineers, and electricians to read and utilize the drawings effectively. This is especially crucial in fields such as electrical work, where precise interpretation of symbols can significantly impact the success of a project.

In contrast, while other terms like "Key" may appear similar and are sometimes used interchangeably with "Legend," they can imply slightly different functions. An "Index" often refers to a list of contents or a directory of items that might be located in a drawing set, and a "Directory" is generally a compiled list of names, addresses, or other information, not specifically related to symbols or technical references in prints.