Harsh call (3)
I believe the answer is:
caw
'harsh call' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for caw that I've seen before include "Crow utterance" , "Sound made by a crow, say" , "Cry of a rook" , "Call like rook" , "Rook's cry" .)