Morose, moody (6)
I believe the answer is:
sullen
I believe this clue is a double definition.
'morose' is the first definition.
(synonyms)
'moody' is the second definition.
(synonyms)
(Other definitions for sullen that I've seen before include "Glowering silently" , "Gloomy and resentful" , "Morose, sulky" , "Dour" , "Gloomy and bad-tempered" .)