Newspaper opinion piece (4)
(Another definition for oped that I've seen is " article in paper".)
(Other definitions for essay that I've seen before include "Attempt; written piece" , "School compeosition" , "Composition; attempt" , "Short formal piece of writing" , "Short treatise" .)
'newspaper opinion piece' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for editorial that I've seen before include "Chief newspaper article" , "Article that states a newspaper's opinion" , "paper item" , "Newspaper item" , "Statement of a newspaper's opinion" .)