Bird after a piece for another (7)
I believe the answer is:
bittern
'bird' is the definition.
(bittern is a kind of bird)
'a piece for another' is the wordplay.
'a piece' becomes 'bit' (bit is a kind of piece).
'for' is a charade indicator (letters next to each other).
'another' becomes 'tern' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'bit'+'tern'='BITTERN'
'after' is the link.
Can you help me to learn more?
(Other definitions for bittern that I've seen before include "Bird with a booming cry" , "Booming marsh bird" , "Marshland bird" , "Bird of marshes" , "Aquatic bird" .)