master copy

Noun

• The copy that serves as the controlling (master) version among a set of copies (as, for example, the master proof to which edits from the authors' proofs are transferred, or an analogous master manuscript with transferred edits).
• An original instance—copy of a document, copy of a digital file (or, metonymically, the disk that contains it), stencil, or otherwise—that serves as a controlling version from which duplicates are made (such as photocopies, printouts, mimeographs, transcluded instances, static content forks, stenciling impression instances, or otherwise).
• A copy from a master (a copy of a masterpiece), done for reasons including training, enjoyment, homage, pastiche, or otherwise.