ending, termination, conclusion - the act of ending something; "the termination of the agreement"

splitsville - separation or breakup or divorce; "after 15 years together they are headed for splitsville"

invalidation, annulment - (law) a formal termination (of a relationship or a judicial proceeding etc)

alteration, change, modification - an event that occurs when something passes from one state or phase to another; "the change was intended to increase sales"; "this storm is certainly a change for the worse"; "the neighborhood had undergone few modifications since his last visit years ago"

falling out, severance, rupture, rift, breach, break - a personal or social separation (as between opposing factions); "they hoped to avoid a break in relations"

break - the occurrence of breaking; "the break in the dam threatened the valley"