Angry cat's sound (4)
I believe the answer is:
hiss
'angry cat's sound' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for hiss that I've seen before include "S-sound of disapproval" , "S-s-snake's s-s-sound?" , "Make snake-like noise" , "Sound of escaping gas" , "Urgent whisper" .)