English to English

adjective (a)

• incapable of being reversed(adj.all)

  Example:
  Irreversible momentum toward revolution.
  

  Antonym:
  reversible
  

  source: wordnet30
• Incapable of being reversed or turned about or back; incapable of being made to run backward; as, an irreversible engine.(adjective)

  source: webster1913