The word "愤怒" is formed by combining two characters, "愤" and "怒", both of which individually convey meanings related to anger. "愤" denotes indignation or resentment, often arising from a sense of injustice, while "怒" refers to direct anger or rage. Together, they create a compound word that intensifies and encompasses the concept of fierce anger, with each character reinforcing the other's semantic field.