How does Roald Dahl use metaphor in "Lamb to the Slaughter"?
Roald Dahl uses metaphor to better describe Mary Maloney in his short story "Lamb to the Slaughter."
A metaphor makes a comparison between two things that are unrelated but share some common characteristics. Working with that definition, a simile is a type of metaphor, because it also makes a comparison in the same manner. A simile simply uses "like" or "as" to make the comparison.
The following is a simile from "Lamb to the Slaughter."
She loved to luxuriate in the presence of this man, and to feel – almost as a sunbather feels the sun – that warm male glow that came out of him to her when they were alone together.
Patrick's very presence is equivalent to the life giving solar energy of the sun for Mary. She practically bathes in his glow.
As for a standard metaphor, the title hints at the extended metaphor of the story. Mary is meek and mild like a lamb. When Patrick delivers his awful news, Mary is devastated. In a way, she and her life have been completely slaughtered by Patrick's betrayal. Then Mary, the lamb, brings an actual leg of lamb to a new slaughter. Patrick's slaughter. The lamb has now become the slaughterer.
In "Lamb to the Slaughter," Dahl uses metaphors in a number of ways. First, the title itself is a metaphor. On one hand, it relates to Patrick Maloney, who becomes a lamb to the slaughter when he is killed by his wife. On the other hand, it can also relate to Mary herself, who is figuratively slaughtered when her husband ends their marriage. Either way, the metaphor alludes to the story's action and is used to foreshadow some of the key events.
Secondly, Dahl uses a metaphor to emphasize Mary's love and devotion toward her husband. Dahl compares Mary's adoration for Patrick to the warm glow felt by a sunbather:
And to feel—almost as a sunbather feels the sun—that warm male glow that came out of him to her when they were alone together.
By doing this, Dahl makes it very clear that Mary is deeply in love and utterly devoted to Patrick. This makes her murder of Patrick all the more shocking to the reader.
Finally, Dahl also uses a metaphor when he compares the leg of lamb to a "steel bar." He does this to emphasize the force of the blow to Patrick's head and to make sure that the reader understands the severity of this action.