mum's the word!

mum's the word

A request or pledge to keep something a secret. Now, I don't want anyone to know that I'm pregnant yet, so mum's the word. Your secret is safe with me. Mum's the word.

ˌmum’s the ˈword!

(informal) used for telling somebody to keep a secret or for telling somebody that you will keep a secret: ‘Nobody must mention this project outside the office. I hope that’s clear.’ ‘We understand, John. Mum’s the word!’

These two idioms refer to the sound you make when your mouth is closed.

Farlex Partner Idioms Dictionary © Farlex 2017

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References in periodicals archive ?

MUM'S the word! Twycross Zoo, near Tamworth, is urging sons and daughters to give their mums a gift this Mother's Day - a visit to see the new babies with their mothers.

Zoo time for Mother's Day

Mum's the word! It's natural to overeat for a few months after a period of starvation.