Bird-like (5)
I believe the answer is:
avian
'bird-like' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for avian that I've seen before include "Like a booby" , "Resembling a bird" , "Lizard with adhesive foot-pads" , "To do with birds - like a dangerous flu" , "Relating to birds" .)