Master anew (7)
I believe the answer is:
relearn
'master anew' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for relearn that I've seen before include "Recommit to memory" , "Become aware of again" , "Mug up once more" , "Get to know again" , "Acquire knowledge again, having forgotten it" .)