Bird for a magician (6)
I believe the answer is:
merlin
This clue is a double definition.
'bird' is the first definition.
(merlin is a kind of bird)
'magician' is the second definition.
(I've seen this before)
'for a' acts as a link.
(Other definitions for merlin that I've seen before include "Legendary magician" , "Magician of Arthurian legend" , "one that cast a spell in Arthur's court" , "Bird of prey - magician" , "Wizard; bird of prey" .)