Bird, female bird (4)
I believe the answer is:
fowl
'bird' is the definition.
(fowl is a kind of bird)
'female bird' is the wordplay.
'female' becomes 'f' (abbreviation).
'bird' becomes 'owl' (owl is a kind of bird**).
'f'+'owl'='FOWL'
(Other definitions for fowl that I've seen before include "Bird, maybe domestic" , "Domesticated bird" , "eg hen" , "Any farmyard bird" , "Domestic birds" .)