"Othello" evildoer (4)
I believe the answer is:
iago
'othello evildoer' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for iago that I've seen before include "Othello's evil counsellor" , "Shakespeare's jealous villain" , "Othello's enemy" , "The villain who tricked Othello" , "Organ stop" .)