mum's the wordINFORMAL
This page is about the conversational phrase mum's the word
You can say this to let someone know that what you've told them is a secret, and they mustn't tell anyone.
- "This is top secret - mum's the word, OK?"
"My lips are sealed, I swear."
- "If I tell you, mum's the word."
"I won't tell anyone else, I promise."
Can also be used to mean "I promise not to tell anyone", as in: "Don't tell anyone, OK?" "Sure. Mum's the word."
If someone says "Mum's the word" while telling you something, you should
Contributor: Matt Errey