1. 
   Keylines
   Lines on mechanical art that show position of photographs or illustrations.
   Found op http://www.printusa.com/glos.htm
   
   
2. 
   Keylines
   Lines on a mechanical or negative showing the exact size, shape and location of photographs or other graphic elements. Also called holding lines.
   Found op http://www.tso.co.uk/solutions/publishingsolutions/printproduction/printglo
   
   
3. 
   Keylines
   Lines on a mechanical or negative showing the exact size, shape, and location of photographs or other graphic elements.
   Found op http://www.e-printing.co.uk/glossary.htm
   
   

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