Placing opposing ideas or words side by side, so that one illuminates the other through contrast.
In Romeo and Juliet
Wisely and slow; they stumble that run fast.
The friar sets "slowly" and "quickly" face to face: whoever goes "wisely and slow" stands against those who "run fast" and stumble. The contrast treats haste as error and slowness as judgment.
Act II: The garden and the wedding, Friar Laurence
O serpent heart, hid with a flowering face!
Act III: Mercutio, Tybalt, and the banishment, Juliet
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