mʌmz ðə wɜːrd
General
informal
intermediate
- Literally:
- The word is 'mum' (silent)
What does "mum's the word" mean?
- Keep this a secret
- Don't tell anyone about this
Examples
- I'm planning a surprise party, so mum's the word.
- Remember, mum's the word about the promotion.
- We're keeping this secret—mum's the word.
Origin
'Mum' is an old English word meaning silent (related to 'mummer'—a silent actor). The phrase dates to at least the 16th century.
How to use it
Friendly way to request secrecy. Often about pleasant surprises or sensitive information.
Similar expressions
keep it secret
don't tell
keep quiet
Opposites
spread the word
tell everyone
Related idioms
- actions speak louder than words
What people do is more important than what they say
- better safe than sorry
It's better to be careful and prevent problems than to take risks
- so far so good
Things have gone well up to now
- easier said than done
Something is more difficult to do than to talk about
- make a long story short
To summarize or get to the point
- to make matters worse
In addition to existing problems
Use it in a practice answer
Try "mum's the word" in a CELPIP-style Speaking or Writing task. The AI feedback tells you whether your word choice worked.