Songbird in wild hurts top of head (6)
I believe the answer is:
thrush
'songbird' is the definition.
(type of songbird)
'wild hurts top of head' is the wordplay.
'wild' indicates anagramming the letters.
'top of' indicates taking the first letters.
The first letter of 'head' is 'h'.
'hurts' anagrammed gives 'thrus'.
'thrus'+'h'='THRUSH'
'in' is the link.
(Other definitions for thrush that I've seen before include "Songbird - fungal infection" , "Infection of the mouth and throat" , "Speckle-breasted songbird" , "Throstle" , "Song bird" .)