Anything carceral has to do with prison or imprisonment. The carceral system includes everything from laws and policing to courts and correctional facilities.
Carceral shares a root with incarcerate — the Latin carcer, meaning "prison." This adjective is primarily used by scholars and journalists to describe the broad legal and political system surrounding imprisonment, including policing, lawmaking, and court systems. Researchers might examine "carceral logic" or "carceral state policy" to discuss how society uses confinement and punishment to enforce rules.