lau ‧ da ‧ num /ˈlɔːd ə nəm $ ˈlɒː-/ BrE AmE noun [uncountable]
[ Date: 1500-1600 ; Language: Modern Latin ; Origin: probably from Medieval Latin lapdanum 'juice obtained from a type of plant' ]
a substance containing the drug ↑ opium , used in the past to control pain and help people to sleep