the green-eyed monster jealousy. literary
☞ Green is traditionally the colour of jealousy, as shown in the previous idiom green with envy and in this one, where the green-eyed monster is jealousy personified. This expression is a quotation from Shakespeare's Othello, where Iago warns: 'O! beware my lord of jealousy; It is the green-eyed monster which doth mock The meat it feeds on'.