Harsh name for a bird (7)
I believe the answer is:
bittern
This might be a double definition.
'harsh name' is the first definition.
Although both the answer and definition are singular nouns, I cannot see how they can define each other.
'bird' is the second definition.
(bittern is a kind of bird)
'for a' acts as a link.
Can you help me to learn more?
(Other definitions for bittern that I've seen before include "'He shall not hear the . . . cry' (Ledwidge)" , "Source of boom" , "flier" , "Marsh bird of the heron family" , "Marshland bird" .)