blue-pencil
[ bloo-pen-suh l ]
/ ˈbluˈpɛn səl /
verb (used with object), blue-pen·ciled, blue-pen·cil·ing or (especially British) blue-pen·cilled, blue-pen·cil·ling.
to alter, abridge, or cancel with or as with a pencil that has blue lead, as in editing a manuscript.
Origin of blue-pencil
First recorded in 1885–90