The term IN A GLOOMY MOOD can be summarized by two words: MOROSE and SULLEN. MOROSE is an adjective that describes someone who is in a bad mood, often characterized by sadness and depression. SULLEN is also an adjective that describes someone who is in a bad mood, but it is more specifically used to describe someone who is in a bad mood due to anger or resentment. Both words are used to describe someone who is in a gloomy mood.