Mum's the word Mum's the word Mum's the word is a popular English idiom. It is related to an expression used by William Shakespeare, in "Henry VI, Part 2". The word “mum” is a slanged version of momme, which was used between 1350-1400 in Middle English with very close to the same meaning: Be silent; Do not reveal "Mum's the word" means to keep silent or quiet. "Mum" is a Middle English word meaning 'silent', and may be derived from the "mummer" who acts without speaking. Note the similar English word "mime" (Old English "mīma", Latin "mimus") meaning silent actor or imitator. The
Old English prestige until the time of the Norman Conquest, after which English ceased for a time to be of importance as a literary language. The history of Old English can be subdivided into: The Old English period is followed by Middle English (12th to 15th century), Early Modern English (c. 1480 to 1650) and finally Modern English (after 1650). Old English should not be regarded as a single monolithic entity, just as Modern English is also not monolithic. It emerged over time out of the many dialects and languages of the colonising tribes, and it is only towards the later Anglo-Saxon