Future resident (6)
I believe the answer is:
intern
'future resident' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for intern that I've seen before include "Often unpaid trainee" , "Imprison the young doctor without trial" , "put in jail" , "Imprison without trial - hospital junior doctor" , "Incarcerate without trial - a junior hospital doctor?" .)