mum's the word

English

Etymology

From mum (“silence”). Recorded since 1704.

Pronunciation

• Audio (General Australian):

  (file)

Phrase

mum's the word

1. (idiomatic) Indicates that something is a secret and not to be divulged.

   She doesn't know anything about it yet, so mum's the word, OK?

   • 1879, Anna Katharine Green, The Leavenworth Case: A Lawyer's Story, G. P. Putnam's Sons, page 256:

     … and that mum is the word till I give you liberty to speak

   • 2024 November 18, Jeremy Levick & Rajat Suresh, “March Madness” (18:44 from the start), in What We Do in the Shadows‎^[1], season 6, episode 7, spoken by Charmaine Rinaldi (Marissa Jaret Winokur):

     “Well, does she know how you feel?” “Honestly, Charmaine, I do not even know how I feel.” “Aw. Well, you should tell her.” “I should tell no one! Can you keep this secret, Charmaine?” “Mm-hmm.” “Good. Because if you don't, I'll kill you in your sleep.” “Okay, mum's the word.”

Translations

indicates that something is a secret

• Catalan: muts i a la gàbia (ca)
• Chinese:

  Mandarin: 保密 (zh) (bǎomì)

• Dutch: mondje dicht
• Estonian: ära kellelegi räägi
• French: motus et bouche cousue (fr)
• German: Behalte es für dich, pst (de) (interjection), pscht (de) (interjection)
• Italian: acqua in bocca (literally “water in [your] mouth”)
• Persian: شتر دیدی ندیدی (šotor didi nadidi)
• Polish: ani mru-mru (pl)
• Portuguese: bico calado, boca de siri (pt) (literally “crab's mouth”)
• Russian: об э́том ни гугу́ (ob étom ni gugú), об э́том молчо́к (ob étom molčók)
• Spanish: chitón (es) (colloquial)
• Welsh: taw piau hi

See also

• breathe a word
• under one's hat