What is "prison bars"

Prison \Pris"on\ (?; 277), n. [F., fr. L. prehensio, prensio, a seizing, arresting, fr. prehendre, prendere, to lay hold of, to seize. See Prehensile, and cf. Prize, n., Misprision.]

1. A place where persons are confined, or restrained of personal liberty; hence, a place or state o? confinement, restraint, or safe custody.

   Bring my soul out of prison, that I may praise thy name.
   --Ps. cxlii. 7.

   The tyrant [AE]olus, . . . With power imperial, curbs the struggling winds, And sounding tempests in dark prisons binds.
   --Dryden.

2. Specifically, a building for the safe custody or confinement of criminals and others committed by lawful authority.

   Prison bars, or Prison base. See Base, n., 24.

   Prison breach. (Law) See Note under 3d Escape, n., 4.

   Prison house, a prison.
   --Shak.

   Prison ship (Naut.), a ship fitted up for the confinement of prisoners.

   Prison van, a carriage in which prisoners are conveyed to and from prison.