let the cat out of the bag 

Idiomatic expression meaning that a secret has been revealed, usually unintentionally, similar to the expression "to spill the beans." Can also be expressed as "the cat is out of the bag."

Bobby let the cat out of the bag when he accidentally mentioned to Amanda the surprise birthday party they were planning on throwing for her.

let the cat out of the bag by VKaizer August 8, 2009

let the cat out of the bag 

(v.) To accidentaly expose secret information one was privy to, forfeiting the entire "game".

Who let the cat out of the bag to that bitch I was using her for business connections?

let the cat out of the bag by Gumba Gumba May 20, 2004

don't let the cat out of the bag 

An idiom for do not tell a secret. Uses figurative language.

"Don't let the cat out of the bag or the party will be ruined!"

don't let the cat out of the bag by JefeOfMasers April 18, 2017