Warden heading off in rage (5)
I believe the answer is:
anger
'rage' is the definition.
(thesaurus)
'warden heading off' is the wordplay.
'warden' becomes 'ranger' (I've seen this before).
'heading off' means to remove the first letter.
'ranger' with its first letter taken away is 'ANGER'.
'in' acts as a link.
(Other definitions for anger that I've seen before include "Range (anag)" , "Emotion" , "Provoke annoyance" , "exasperation" , "Strongly annoy" .)