Long-billed marsh bird (5)
I believe the answer is:
snipe
'long-billed marsh bird' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for snipe that I've seen before include "Criticise" , "From concealed position, shoot" , "The bird to shoot from cover" , "To pick off soldiers, say" , "Verbal criticism" .)