The bird flying out is able to (6)
I believe the answer is:
toucan
'the bird' is the definition.
(toucan is a kind of bird)
'flying out is able to' is the wordplay.
'flying' indicates an anagram (letters fly around into new positions).
'is able to' becomes 'can' (if you can do something you are able to do it).
'out' is an anagram of 'tou'.
'tou'+'can'='TOUCAN'
(Other definitions for toucan that I've seen before include "Brightly-coloured tropical bird with large beak" , "Fruit-eating bird" , "Tropical bird with large bill" , "Bird with a large brightly-coloured bill" , "Showy bird" .)