1.
jail; prison cell; gaol
A room or building where prisoners are kept. Often evokes a traditional or historical image of confinement, such as cells with bars.
Usage
牢屋 has a somewhat old-fashioned or dramatic tone. In modern everyday language, 刑務所 (prison) is the standard term for penal institutions. 牢屋 is commonly used in historical contexts, fiction, and colloquial expressions.