Preserved dead bodies, especially from ancient Egypt, or informally, mothers.
From Arabic 'mumiya' (mummy), derived from 'mumm' (wax or bitumen), because of the bituminous substances used in preservation. First used for Egyptian mummies, later became slang for mothers in British English.
Ancient Egyptians didn't actually use the word 'mummy'—that's what Arabs called bitumen, and when Europeans discovered preserved bodies covered in dark bituminous substances, they adopted the Arabic word, creating a thousand-year-long mistranslation!
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