Nickname for the young Darth Vader (3)
I believe the answer is:
ani
'nickname for the young darth vader' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for ani that I've seen before include "Bird of the cuckoo family" , "Black cuckoo" , "Indigo dye." , "Black bird" , "Tropical bird" .)