Word Origin & History
1560s, from M.E. mum, mom "silent" (late 14c.), imitative of the sound made with closed lips, as indicative of unwillingness or inability to speak. Phrase mum's the word is first recorded 1704.
abbreviation of chrysanthemum, first attested 1924 in the jargon of gardeners.
1823, pet word for "mother," short for mummy. In British sociology, used from 1957 in ref. to "the working class mother as an influence in the lives of her children."