Big bird Down Under (3)
I believe the answer is:
emu
'big bird down under' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for emu that I've seen before include "that doesn't get off the ground" , "Hull's character" , "European project" , "it can't get off the ground" , "Australian non-flyer" .)