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| Let the Cat out of the Bag |
Let the cat out of the bag means to reveal a secret or disclose information that was supposed to remain hidden, usually by accident or without intending to do so.
This common English idiom is often used when someone unintentionally shares confidential news, surprises, plans, or private information before the appropriate time.
Part of Speech: Idiom
Difficulty Level: Intermediate
Pronunciation: /let ðə kæt aʊt əv ðə bæɡ/
When a person lets the cat out of the bag, they accidentally expose a secret or reveal something that others wanted to keep private.
The idiom is frequently used in everyday conversations, business settings, social situations, and storytelling.
The phrase “let the cat out of the bag” is just one example of animal-based expressions. For more such phrases, check out Cat Idioms.
More idioms about truth and lies: Revealing a secret is one thing, but being caught in a lie is another. Learn the meaning and history of liar liar pants on fire as well.
Some similar expressions and words include:
Words and phrases with the opposite meaning include:
The exact origin of this idiom is uncertain, but one popular theory traces it back to old marketplaces in Europe. Unscrupulous sellers were said to replace valuable piglets with less valuable cats inside bags. If the bag were opened before the sale was completed, the deception would be exposed, and the "cat would be let out of the bag".
Although historians debate the accuracy of this explanation, the phrase has been used in English since at least the 18th century and has come to mean revealing a hidden secret or truth.
You may also like → 50 Common English Idioms for Daily Conversation
This idiom is commonly used when:
Birthday Party:
Someone tells the birthday person about the surprise celebration beforehand.
Workplace:
An employee reveals information about a project before the official announcement.
Family Gathering:
A relative accidentally shares news that was meant to remain secret.
❌ He opened the bag and let the cat out literally.
(This refers to an actual cat, not the idiom.)
✅ He let the cat out of the bag about the surprise gift.
(This correctly uses the idiom to mean revealing a secret.)
If you enjoy learning English idioms, you may also like:
Think of a secret as something safely locked inside a bag. Once someone opens the bag and the cat jumps out, everyone can see what's inside. In the same way, when you let the cat out of the bag, a secret is no longer a secret.
| Expression | Let the Cat out of the Bag |
|---|---|
| Meaning | To reveal a secret, usually accidentally |
| Type | Idiom |
| Difficulty | Intermediate |
| Common Use | Secrets, surprises, confidential information |
| Similar Idioms | Spill the Beans, Let Slip, Give Away |
Example: Rohan accidentally let the cat out of the bag about the surprise anniversary celebration.
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