Butcher bird (6)
I believe the answer is:
shrike
'butcher bird' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for shrike that I've seen before include "Shriek like kind of bird" , "Butcher bird" , "Songbird with a heavy hooked bill" , "Butcherbird" , "Predatory songbird" .)