Terrible anger shown by Democrat (4)
I believe the answer is:
dire
'terrible' is the definition.
('dire' can be a synonym of 'terrible')
'anger shown by democrat' is the wordplay.
'anger' becomes 'ire' ('ire' can be a synonym of 'anger'**).
'shown by' is a charade indicator (letters next to each other).
'democrat' becomes 'd'.
'ire' after 'd' is 'DIRE'.
(Other definitions for dire that I've seen before include "Portentous" , "Really awful kind of ride" , "Dreadful; grim" , "'Dreadful, terrible (4)'" , "Fearful" .)