the act of leaving a country, political party, etc. to go to another one脱离,退出,叛逃(国家或政党等)
Over the years there were hundreds of defections to the West/defections from the East.这些年来发生了数百起向西方/从东方叛逃的事件。
Recent changes in policy have resulted in large-scale defection from the party.最近的政策变化导致了大规模的党员倒戈行为。