Ostrich-like bird
I believe the answer is:
rhea
'ostrich-like bird' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for rhea that I've seen before include "Fast-running flightless bird" , "New World ostrich" , "South American bird resembling the ostrich" , "nonflyer" , "Small 'ostrich'" .)