The word 愤怒 is formed by combining two characters, 愤 and 怒, which each individually contain the core meaning of "anger". 愤 conveys a sense of inner, smoldering indignation or resentment, often arising from a sense of injustice. 怒 expresses a more immediate, explosive, and visibly manifested rage. When placed side-by-side, they do not create a new meaning from unrelated parts, but rather reinforce and compound each other, merging into a single, powerful concept that encompasses the full emotional range of intense anger, from its deep-seated, brooding origin to its fiery, outward expression.