Doctor gets sum wrong for bongos, say (5)
I believe the answer is:
drums
'bongos say' is the definition.
(bongo is a kind of drum)
'doctor gets sum wrong' is the wordplay.
'doctor' becomes 'dr' ('Dr' can be a synonym of 'doctor'**).
'gets' is a charade indicator (letters next to each other).
'wrong' indicates anagramming the letters.
'sum' is an anagram of 'ums'.
'dr'+'ums'='DRUMS'
'for' is the link.
(Other definitions for drums that I've seen before include "Percussion instruments" , "Containers" .)