This writer goes to doctor to get a note (4)
I believe the answer is:
memo
'a note' is the definition.
(memo is a kind of note)
'this writer goes to doctor' is the wordplay.
'this writer' becomes 'me' (the person who is writing these clues).
'goes to' means one lot of letters go next to another.
'doctor' becomes 'mo' (medical officer**).
'me'+'mo'='MEMO'
'to get' acts as a link.
(Other definitions for memo that I've seen before include "Inter-office note" , "Office note" , "Note written as a reminder" , "Written business message, in short" , "A brief record of events" .)