master copy

[master copy] {n.} 1. A perfect text to which all copies are madeto conform; a corrected version used as a standard by printers.

Themaster copy must be right, because if it isn't, the mistakes in itwill be repeated all through the edition.

2. A stencil from whichother copies are made.

Mr. Brown told his secretary to save themaster copy so that they could run off more copies whenever theyneeded them.

The master copy was too light so many of the copiesdidn't come out clear.