The phrase ‘mum’s the word’ is used to express the idea of keeping quiet or not revealing information. Its origins can be traced back to Middle English, where ‘mum’ meant ‘silent’ or ‘quiet.’ This term likely derives from the ancient practice of keeping secrets and was popularized in literature over the centuries.
One notable instance of its use can be found in Shakespeare’s play ‘Henry VI, Part 2,’ where the phrase ‘mum’ is employed to indicate silence in the context of secrecy.
Over time, ‘mum’s the word’ evolved into a common idiom in the English language, conveying a sense of discretion regarding information that should not be shared. Today, it often serves as a playful reminder to keep things under wraps, whether it’s a surprise party or a personal secret.