Definition of blueline:
(n) :
A reproduction of the material submitted for printing, computer-generated or printed from film, provided to the customer for approval before the material is printed.
(v) :
To create the bluelines for material that is about to be printed.
(v) :
To check the bluelines before printing material.
(v) :
(surgery) To mark on a patient's body where the surgical incision is to be made.
(v) :
To veto a portion of a budget.
(v) :
To edit a legal document.