WordNet (r) 3.0 (2006):

breakout
    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:

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