internship (n.)

"one working under supervision as part of professional training," originally "assistant resident physician, doctor in training in a hospital," 1879, American English, from French interne "assistant doctor," noun use of interne "internal," from Latin internus "within, inward" (see internal). Extended to other professions (originally teaching) from 1963 in reference to one under training and acquiring practical experience.

word-forming element meaning "quality, condition; act, power, skill; office, position; relation between," Middle English -schipe, from Old English -sciepe, Anglian -scip "state, condition of being," from Proto-Germanic *-skepi- (cognates: Old Norse -skapr, Danish -skab, Old Frisian -skip, Dutch -schap, German -schaft), from *skap- "to create, ordain, appoint," from PIE root *(s)kep-, forming words meaning "to cut, scrape, hack" (see shape (v.)). It often forms abstracts to go with corresponding concretes (friend/friendship, etc.).