General synonyms:
* Depressing: This is a very common synonym for gloomy, emphasizing the negative emotional impact.
* Dismal: This emphasizes a sense of hopelessness and despair.
* Sombre: This implies a feeling of seriousness and sadness, often associated with mourning or reflection.
* Melancholy: This suggests a deep sadness and a sense of longing.
* Cheerless: This emphasizes the lack of happiness or joy.
* Dark: This synonym highlights the absence of light and brightness, both literally and figuratively.
More specific synonyms:
* Bleak: This suggests a feeling of emptiness and desolation.
* Despondent: This emphasizes a loss of hope and courage.
* Foreboding: This implies a sense of impending danger or misfortune.
* Oppressive: This suggests a feeling of weight and heaviness.
* Morose: This implies a sullen and brooding mood.
* Downcast: This emphasizes a sense of sadness and dejection.
The best synonym for "gloomy" will depend on the specific context in which you are using the word.