Doctor, doctor -- I'd come! (6)
I believe the answer is:
medico
'doctor' is the definition.
(synonyms)
'doctor i'd come' is the wordplay.
'doctor' indicates an anagram.
'id'+'come'='idcome'
'idcome' with letters rearranged gives 'MEDICO'.
(Other definitions for medico that I've seen before include "Health practitioner" , "quack" , "Doctor" .)