Meaning & use
mum's the word
Last updated
UK/ˌmʌmz ðə ˈwɜːd/
US/ˌmʌmz ðə ˈwɜːrd/
Meaning
phrasefixed phraseinformal
Said to agree to keep a secret, or to tell someone not to reveal it.
Grammar: Used as a short remark or reply; it does not change form.
Patterns
- Mum's the word about something
We are planning a surprise party for Dad, so mum's the word.
Mum's the word on the new job until it is official.
'I won't tell her,' he whispered. 'Mum's the word.'
Common combinations
- mum's the word about
- Mum's the word about the gift.
- remember, mum's the word
- Remember, mum's the word until Friday.
- keep mum
- She decided to keep mum about the plan.
- say mum's the word
- He winked and said mum's the word.
Synonyms and how they differ
- keep it quiet
- Keep it quiet is plain and direct, whereas mum's the word is a playful, old-fashioned saying.
- don't breathe a word
- Don't breathe a word is a stronger warning not to tell anyone.
- my lips are sealed
- My lips are sealed is a promise made by the speaker, while mum's the word can be a reminder to others too.
- between us
- Between us is a shorter way to ask that something stay private.
Opposites
Word family
Commonly confused: mum's the word or mum?
mum's the word vs mum
In British English mum also means mother, but in this phrase it is an old word meaning silent.
Practice
What do you mean when you say 'mum's the word'?
Choose one answer.
Mum's the word means keep quiet about something. Here mum is an old word for silent, not mother.
Make it your own
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