Top politicians can bite terribly (7)
I believe the answer is:
cabinet
'top politicians' is the definition.
'can bite terribly' is the wordplay.
'terribly' is an anagram indicator.
'can'+'bite'='canbite'
'canbite' with letters rearranged gives 'CABINET'.
(Other definitions for cabinet that I've seen before include "Furniture item or collective government ministers" , "Piece of furniture with doors, shelves and drawers" , "Collective noun for senior ministers" , "Can bite (anag.)" , "high-level meeting" .)