1. withdrawing support or help despite allegiance or responsibility;

   "his abandonment of his wife and children left them penniless"
   

2. the state of having rejected your religious beliefs or your political party or a cause (often in favor of opposing beliefs or causes)

1. 背叛：在囚犯困境模式下,每一个行为者都有优势战略(dominantstrategy),即背叛(defection). 因为缺乏对方行动的信息,每一方都试图通过欺诈获得最大的利益,而不管另一方获益与否. 因此,最终结果是双方都背叛. 然而不幸的是,

2.

2. 背信：在囚徒两难中,假如合作,那么双方的收益最大,但是理性利己的博弈者最终还是会做出背信(defection)的行为,就是基于双方分析对方采取合作和背信策略的可能性,计算自己在合作和背信策略下的期望收益,进行比较,最后采取使自己的期望收益最大的,

3. 缺点过失变节：defect 缺陷 |defection 缺点 过失 变节 |defection 缺点过失变节

4. 缺点：defect 过失 |defection 缺点 | defective verb 变化不完全的动词