"Alice in Wonderland" bird (4)
I believe the answer is:
dodo
'alice in wonderland bird' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for dodo that I've seen before include "Extinct bird of Mauritius, very dead" , "Proverbially extinct bird" , "Square" , "Old-fashioned person" , "Old bird" .)