Stretch your neck to see a bird (5)
I believe the answer is:
crane
'stretch' is the definition.
(craning is a kind of stretching)
'your neck to see a bird' is the wordplay.
I cannot quite understand how this works, but
'see' could be 'c' (the word for the letter, according to Chambers) and 'c' is found in the answer.
'a' could be 'an' and 'an' is found in the answer.
The remaining letters 're' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for crane that I've seen before include "Bird; hoister" , "Device for picking up" , "Lifting structure" , "Tall wading bird can lift heavy loads" , "Bird; dockside machine" .)