资料来源 : Webster's Revised Unabridged Dictionary (1913)

Jail \Jail\, n. [OE. jaile, gail, gayhol, OF. gaole, gaiole,
   jaiole, F. ge[^o]le, LL. gabiola, dim. of gabia cage, for L.
   cavea cavity, cage. See {Cage}.]
   A kind of prison; a building for the confinement of persons
   held in lawful custody, especially for minor offenses or with
   reference to some future judicial proceeding. [Written also
   {gaol}.]

         This jail I count the house of liberty.  --Milton.

   {Jail bird}, a prisoner; one who has been confined in prison.
      [Slang]

   {Jail delivery}, the release of prisoners from jail, either
      legally or by violence.

   {Jail delivery commission}. See under {Gaol}.

   {Jail fever} (Med.), typhus fever, or a disease resembling
      it, generated in jails and other places crowded with
      people; -- called also {hospital fever}, and {ship fever}.
      

   {Jail liberties}, or {Jail limits}, a space or district
      around a jail within which an imprisoned debtor was, on
      certain conditions, allowed to go at large. --Abbott.

   {Jail lock}, a peculiar form of padlock; -- called also
      {Scandinavian lock}.

资料来源 : WordNet®

jail delivery
     n : the use of force to liberate prisoners