Doctor nursed a performer (7)
I believe the answer is:
danseur
'performer' is the definition.
(male ballet dancer)
'doctor nursed a' is the wordplay.
'doctor' indicates anagramming the letters.
'nursed'+'a'='nurseda'
'nurseda' is an anagram of 'DANSEUR'.
(Other definitions for danseur that I've seen before include "Ballerina's partner" , "Male ballet dancer, partner of a ballerina" , "Maybe Nureyev" , "One may need to be on one's toes" , "Asunder (anag); ballet performer" .)