etiquette
noun [ U ] uk/ˈet.ɪ.ket/ us/ˈet̬.ɪ.kɪt/
礼仪，礼节;规范，规矩
the set of rules or customs that control accepted behaviour in particular social groups or social situations
Social etiquette dictates that men cannot sit while women are standing. （社交）礼仪要求在女士站立时，男士不能入座。
Diplomatic etiquette forbids calling for the death of a national leader. 外交礼节禁止公开要求处死国家领导人。