Saying one thing through another, without a word of comparison: instead of saying that something is like another thing, one says that it is. The image transfers to the subject the qualities of the thing with which it is identified.
In Macbeth
Come, you spirits / That tend on mortal thoughts, unsex me here, / And fill me from the crown to the toe top-full / Of direst cruelty. [...] Come to my woman's breasts / And take my milk for gall, you murd'ring ministers
By saying that her milk "is now gall," she joins tenderness and poison in a single image. What would feed a child turns bitter, and the image shows that she asks for a change of nature.
Act I: The Prophecy and the Temptation, Lady Macbeth
Methought I heard a voice cry 'Sleep no more! / Macbeth does murder sleep,' the innocent sleep, / Sleep that knits up the raveled sleave of care, / The death of each day's life, sore labor's bath, / Balm of hurt minds, great nature's second course, / Chief nourisher in life's feast [...] 'Glamis hath murdered sleep, and therefore Cawdor / Shall sleep no more. Macbeth shall sleep no more.'
Act II: The Murder of Duncan, Macbeth
If 't be so, / For Banquo's issue have I filed my mind; / For them the gracious Duncan have I murdered, / Put rancors in the vessel of my peace / Only for them [...]
Act III: The King Ruled by Fear, Macbeth
We have scorched the snake, not killed it. [...] Better be with the dead, / Whom we, to gain our peace, have sent to peace, / Than on the torture of the mind to lie / In restless ecstasy.
Act III: The King Ruled by Fear, Macbeth
He has no children. All my pretty ones? / Did you say all? O hell-kite! All? / What, all my pretty chickens and their dam / At one fell swoop?
Act IV: Deceptive Prophecies and Massacre, Macduff
Tomorrow, and tomorrow, and tomorrow, / Creeps in this petty pace from day to day, / To the last syllable of recorded time; [...] Life's but a walking shadow, a poor player / That struts and frets his hour upon the stage / And then is heard no more. It is a tale / Told by an idiot, full of sound and fury, / Signifying nothing.
Act V: Sleepwalking, Birnam, and the Fall, Macbeth
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