(n.) The act or the result of betraying.

Judas kiss abuse apostasy babbling backsliding bad faith blabbering blabbing bolt breach of faith breakaway communication leak criminal assault dead giveaway debauchment defection defilement defloration deflowering dereliction deserter desertion despoilment disclosure disloyalty divulgation divulgement divulgence divulging double cross evulgation faithlessness giveaway going over indiscretion leak letting out obvious clue perfidy priapism rape ratting ravage ravishment recidivation recidivism recreancy revelation schism secession seducement seduction sellout sexual assault telltale telltale sign traitorousness treachery treason turning traitor unwitting disclosure violation walkout