Cutout 
In negative flat preparation, openings cut through the goldenrod or masking paper to produce the exposure areas needed on the negatives for plate exposure; also called Window.
Cutter Dust 
Residue resulting from the paper cutting operation, which may interfere in the printing process.
Cutter Wrinkles 
Creases or folds in the sheet, usually running at a slight angle to machine direction; may vary in size and appear at random.
Cyan 
Process Blue; one of the four process colors.