Largest-wingspan bird (9)
I believe the answer is:
albatross
'largest-wingspan bird' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for albatross that I've seen before include "Great hole" , "See 7" , "Ocean bird; a burden (round neck)" , "Southern hemisphere seabird" , "As Borstal is adapted for a big bird" .)