Piggish noise (4)
I believe the answer is:
oink
'piggish noise' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for oink that I've seen before include "What you get from pen" , "Sound made by a pig" , "farmyard noise" , "Beastly noise" , "what we hear from Berkshire?" .)