turn back on
背弃、对某人不再支持、对某事不再参与
口语·表达背弃或拒绝
英文释义
to abandon or reject someone or something
例句
He turned his back on his friends when they needed help.
典故来源
源于转身离开的肢体动作，象征拒绝或抛弃某人或某事。