The Collaborative International Dictionary of English v.0.48:

jailbreak \jailbreak\ n.
   an escape from jail; as, five prisoners escaped in a
   coordinated jailbreak.

   Syn: break, breakout, gaolbreak, prisonbreak,
        prison-breaking.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

jailbreak
    n 1: an escape from jail; "the breakout was carefully planned"
         [syn: break, breakout, jailbreak, gaolbreak,
         prisonbreak, prison-breaking]

Moby Thesaurus II by Grady Ward, 1.0:

24 Moby Thesaurus words for "jailbreak":
   break, breakout, deliverance, delivery, emergence, escape,
   escapism, evasion, extrication, flight, freeing, getaway, issuance,
   issue, leak, leakage, liberation, outlet, prisonbreak, release,
   rescue, riddance, setting-free, vent