See somber in Webster's New World Roget's A-Z Thesaurus II
adjective
Dark and depressing:
black, bleak, blue, cheerless, dark, desolate, dismal, dreary, gloomy, glum, joyless, tenebrific. See happy, lightFull of or marked by dignity and seriousness:
earnest1, grave2, sedate, serious, sober, solemn, staid. See attitude, heavy
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