The employees were indignant about how the bonuses were allocated.
Tips
history
Traceable to Xu Song's Tang-dynasty 《建康实录》: 自尔愤愤不平，每酒后辄咏魏武帝乐府 — describing a man who, seething with resentment, would recite Cao Cao's yuefu songs whenever drunk. The 《汉书·刘据传》 has the earlier variant 忿忿.
usage
Describes lingering, simmering anger over something unjust — not a momentary flash of rage. Often appears with 对 (towards) or used adverbially with 地.
