Definition of meconium in English:



  • The dark green substance forming the first feces of a newborn infant.

    ‘Infants who pass thin meconium, which is yellow to light green and watery, are more likely to be healthy at birth.’
    • ‘In 95 percent of newborns, meconium is passed by 24 hours of age.’
    • ‘The question as to why some infants may discharge meconium in times of stress and other infants do not has not been well studied.’
    • ‘A common presentation is failure to pass meconium in the first 24 hours coupled with a gradual onset of abdominal distension and vomiting.’
    • ‘Urine samples were collected from the women and meconium samples were collected from each baby.’



/məˈkōnēəm/ /məˈkoʊniəm/


Early 17th century (denoting poppy juice): from Latin ‘opium, faeces of a newborn’, from Greek mēkōnion, from mēkōn ‘poppy’. The sense ‘faeces of a newborn’ dates from the early 18th century.