chip on shoulder
对待或与他人交往时持有敌意、情绪激动或怨恨
口语·形容怀有敌意或怨恨
英文释义
to have a grudge or a sense of resentment
例句
He always has a chip on his shoulder about his past failures.
典故来源
源自19世纪美国习俗，男孩把木屑放在肩上挑衅别人打掉，以此挑起争斗，后引申为怀恨在心。