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.
Words like “let the cat out of the bag” are exactly the kind of vocabulary our English vocabulary size test measures — find out how many English words you know.
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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