Setting ideas or opposing words side by side, so that one illuminates the other through contrast.
In Othello
An old black ram / Is tupping your white ewe.
"Black" and "white" are placed face to face in the same image. The opposition of colors makes racial difference the center of the insult, without Iago needing to say it in so many words.
Act I: Venice, the night accusation and the Senate hearing, Iago
Not to pick bad from bad, but by bad mend!
Act IV: Humiliation and the willow song, Desdemona
I can again thy former light restore, / Should I repent me; but once put out thy light, [...] I know not where is that Promethean heat / That can thy light relume.
Act V: The ambush, the murder and the revelation, Othello
I kissed thee ere I killed thee. No way but this, / Killing myself, to die upon a kiss.
Act V: The ambush, the murder and the revelation, Othello
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