Can be the return of the exile place of Napoleon (4)
I believe the answer is:
able
'can' is the definition.
(I've seen this before)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for able that I've seen before include "showing talent" , "With the required capacities" , "Having the ability to do something" , "Well-equipped" , "Qualified - expert" .)