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 was identified.
In Othello
An old black ram / Is tupping your white ewe.
Iago reduces Othello and Desdemona to animals: the "old black ram" covering the "white ewe" presents the marriage as animal mating. The image does not describe, it wounds, and it was made to kindle Brabantio's fury.
Act I: Venice, the night accusation and the Senate hearing, Iago
I have 't. It is engendered. Hell and night / Must bring this monstrous birth to the world's light.
Act I: Venice, the night accusation and the Senate hearing, Iago
O, you are well tuned now! / But I'll set down the pegs that make this music, / As honest as I am.
Act II: Cyprus, the storm and Cassio's fall, Iago
And out of her own goodness make the net / That shall enmesh them all.
Act II: Cyprus, the storm and Cassio's fall, Iago
O, beware, my lord, of jealousy! / It is the green-eyed monster, which doth mock / The meat it feeds on.
Act III: The temptation and the handkerchief, Iago
A hornèd man's a monster and a beast.
Act IV: Humiliation and the willow song, Othello
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
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