an organ near the stomach that produces and cleans the body's blood

a feeling of anger and disagreement

mainly UK She threatened, in a fit/burst of spleen, to resign. 她一时恼怒，威胁说要辞职。

Shareholders used the conference as an opportunity to vent their spleen on (= get angry with) the Board of Directors. 股东们把大会当成了向董事会泄愤的机会。