Large-billed tropical bird (6)
I believe the answer is:
toucan
'large-billed tropical bird' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for toucan that I've seen before include "Bird with large, colourful bill" , "Tropical American bird with immense beak" , "arboreal dweller" , "Sounds as if a pair is able for the tropical bird" , "Colourful bird, big bill" .)