牢獄|ろうごくrougoku[0]heiban (flat)

1. nounprison; jail; gaol
   囚人しゅうじんが牢獄ろうごくから逃にげた。↗

   A convict has escaped from prison.

• Synonym刑務所けいむしょFormalFormal: the standard modern prison where convicts serve sentences, and the official legal name. 「牢獄」 is old-fashioned and literary, and can be a metaphor for bondage.
• Synonym監獄かんごくWrittenWritten prose. An older legal name for 「刑務所」; now mostly historical, as in 「網走監獄」.
• Synonym獄舎ごくしゃWrittenWritten prose. The buildings that house prisoners; rare, and mostly in historical description.
• Synonym牢屋ろうやNeutralA jail, common in speech; evokes the Edo period and period dramas, as in 「牢屋に入れる」.
• Synonym牢ろうNeutralOld-fashioned on its own, mostly in 「牢に入る」; can also mean firm or solid.
• Synonym獄屋ごくやWrittenWritten prose. A prison building; rare, and synonymous with 「獄舎」.
• Related拘置所こうちしょFormalFormal. Holds people not yet sentenced and death-row inmates, so its purpose differs from 「刑務所」.
• Related獄ごくWrittenWritten prose. Mostly a combining form in words like 「投獄」 and 「脱獄」 rather than standing alone.
• Related獄所ごくしょWrittenWritten prose. A place of confinement; rare and old-fashioned.
• Relatedブタ箱ぶたばこCasualColloquial slang for a police cell or lockup, contemptuous or joking, as in 「ブタ箱に放り込む」; 「牢獄」 is more literary.

For a modern prison say 「刑務所」; for untried detainees, 「拘置所」. 「牢獄」 itself suits literary or metaphorical contexts like 「心の牢獄」; 「牢屋」 fits period settings, 「監獄」 is now historical, and 「ブタ箱」 is slang for a lockup.

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

1. 捕とらえた罪人ざいにんを収容しゅうようする建物たてもの。