The most common and most likely answer to this crossword clue is the 10 letter word GREENSHANK
I've seen this crossword clue in The Times
G
R
E
E
N
S
H
A
N
K
More clues leading to the result GREENSHANK
Buddy explains!
The straight part
We know that "Bird" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case bird = greenshank.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does GREENSHANK mean?
GREENSHANK noun- A wading bird, Tringa nebularia, that has long greenish legs and is native to Eurasia.