apostasy/əˈpɔstəsɪ; ə`pɑstəsɪ/ n(a) [U] abandoning one's religious beliefs, principles, political party, etc 放弃宗教信仰; 背教; 变节; 脱党.(b) [C] instance of this 背教; 变节; 脱党.
牛津英汉双解词典