in ‧ tern ‧ ist /ˈɪntɜːnəst, ˈɪntɜːnɪst $ -ɜːr-/ BrE AmE noun [countable] American English
[ Date: 1900-2000 ; Origin: internal (medicine) + -ist ]
a doctor who has a general knowledge about all illnesses and medical conditions of organs inside your body, and who treats illnesses that do not need operations