Ballerina role, perhaps (4)
I believe the answer is:
swan
'ballerina role perhaps' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for swan that I've seen before include "Large aquatic bird" , "Royal bird" , "Graceful bird" , "Large water bird" , "The Ugly Duckling's outcome" .)