verb phrase🎓 English idiom

let the cat out of the bag

to reveal a secret

What it means

To reveal a secret carelessly or by mistake, especially one that was meant to be kept hidden. It's used when information slips out and can no longer be taken back.

Examples

  • He let the cat out of the bag about the new baby too early.
  • Try not to let the cat out of the bag before the official announcement.
  • Someone let the cat out of the bag and ruined the surprise.
  • I let the cat out of the bag by mentioning her gift in front of her.

Where it comes from

The origin is uncertain; a popular theory says dishonest market sellers substituted a worthless cat for a piglet in a sack, and the trick was exposed when the cat was let out. The phrase appears in English by the 1700s.

Related idioms

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