Learner, apprentice (7)
I believe the answer is:
trainee
I believe this is a double definition.
'learner' is the first definition.
(I've seen this before)
'apprentice' is the second definition.
(someone undergoing training)
(Other definitions for trainee that I've seen before include "Apprentice" , "Student" , "A beginner in Aintree" , "Job learner" , "Person under instruction" .)