Impressive bird one better than eagle (9)
I believe the answer is:
albatross
'impressive bird' is the definition.
'albatross' can be an answer for 'bird' (albatross is a kind of bird). I am unsure of the 'impressive' bit.
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for albatross that I've seen before include "As Borstal is adapted for a big bird" , "Spectacular hole" , "Large oceanic bird" , "Long-winged sea-bird, a constant burden" , "can be an encumbrance" .)