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.