Editor's "don't delete" (4)
I believe the answer is:
stet
'editor's don't delete' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for stet that I've seen before include "Let it remain (printing)" , "Cancellation of correction" , "leave things as they were" , "Ignore crossing" , "Printer's annotation - let it stand" .)