Hound or badger (3)
I believe the answer is:
nag
This clue is a double definition.
'hound' is the first definition.
(I've seen this in another clue)
'badger' is the second definition.
(both can mean to annoy or complain at)
(Other definitions for nag that I've seen before include "Scold persistently, annoy" , "trouble constantly" , "Old Arab maybe" , "Horse; keep scolding" , "Worry constantly" .)