taru-adjective, adverb taking the 'to' particle
dark; gloomy; somber; depressing
Describes a situation, mood, or prospect that is bleak, hopeless, or deeply discouraging. Often used in literary or formal contexts. Functions as a taru-adjective (〜たる) or adverbially with と.
戦争で国の未来は暗澹たるものだった。
The country's future was bleak because of the war.
彼は暗澹とした表情でうつむい
He hung his head with a gloomy expression.
Variant kanji form using 憺 instead of 澹. Rarely used.
暗い is the common word for 'dark' (lack of light) or 'gloomy' (mood). 暗澹 is more literary and emphasizes a deep, hopeless bleakness, often about situations or futures.
陰鬱 also means 'gloomy' or 'dismal', but can describe weather, atmosphere, or personality. 暗澹 is stronger and more often used for prospects or abstract conditions.
From Chinese 暗澹 (àndàn), meaning 'dim' or 'gloomy'. The Japanese reading is on'yomi. The second character 澹 is rare in modern Japanese and is sometimes replaced by kana.