Extract from Othello - 'green-eyed monster' (4)
I believe the answer is:
ogre
'monster' is the definition.
(fairy tale monster)
'extract from othello green-eyed' is the wordplay.
'extract from' indicates a hidden word (some letters extracted from the clue).
'OGRE' can be found hidden inside 'othello green eyed'.
(Other definitions for ogre that I've seen before include "Cruel, fearsome person" , "Terrifying monster" , "Ergo (anag.)" , "Has a monstrous role" , "Fierce giant" .)