孤独|こどくkodoku[0]heiban (flat)

1. na-adjective, no-adjectivesolitude; loneliness; isolation
   私はこの上うえなくさびしく、孤独こどくだ。↗

   I am as sad and lonely as can be.

• Synonym一人ぼっちひとりぼっちCasualColloquial: all by oneself, with no one around (「一人ぼっちになる」); stresses the situation of being alone.
• Related寂しいさびしいNeutralThe most common word in everyday speech: feeling lonely (「一人で寂しい」). It is about the emotion, while 「孤独」 is about the circumstances.
• RelatedわびしいWrittenWritten/formal prose: bleak and dreary, a heart with nothing to console it (「侘しい一人暮らし」); 「孤独」 stresses being alone with no one to rely on.
• Relatedうら寂しいうらさびしいNeutralA faint, lingering loneliness that carries a certain mood or atmosphere (「うら寂しい夕暮れ」).
• Related心寂しいこころさびしいWrittenSame as the entry above: 「心寂しい」 is simply another way of writing 「うら寂しい」, with the same meaning.
• Related孤こWrittenWritten/formal prose: an orphan, or by extension a person with no companions; 「孤独」 is the state of being alone.
• Related物寂しいものさびしいWrittenWritten/formal prose: an inexplicable sense of desolation or stillness (「物寂しい秋」).
• Antonym交流こうりゅうNeutralExchange and interaction between people; only a related concept, not a true opposite — someone with plenty of interaction can still be lonely.
• Antonym団欒だんらんWrittenWritten/formal prose: family and close ones gathered happily together; the direct opposite of 「孤独」.

Use 「孤独」 for the state of being alone with no one to rely on (「孤独死」「孤独を感じる」). For the feeling of loneliness, say 「寂しい」; for being all alone, 「一人ぼっち」; for a bleak, desolate feel, 「侘しい」. The opposite is 「団欒」; 「交流」 is only loosely related.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. 孤こと独り身ひとりみ。両親りょうしんを失うしなった子供こどもと、老おいて子供こどものいない年寄としより。
2. 身寄みよりや頼たよりになる相手あいてが無なく、独ひとりであること。
3. 身寄みよりや頼たよりになる相手あいてが無なく、独ひとりである。