End in a bad mood (4)
I believe the answer is:
doom
'end' is the definition.
(thesaurus)
'bad mood' is the wordplay.
'bad' is an anagram indicator.
'mood' with letters rearranged gives 'DOOM'.
'in a' is the link.
(Other definitions for doom that I've seen before include "Disastrous fate" , "Mood of death or ruin" , "Sentence" , "Fate; ruin" , "Curse" .)