The compound word "主人公" is formed through a morphological process where the root "主人" (zhǔrén), meaning "master" or "host," is combined with the honorific suffix "公" (gōng), which denotes respect or formality. This structure follows a common pattern in Chinese where a title or core concept is modified by an affix to create a more specific or elevated term. Historically, "公" was used in aristocratic titles, and its addition to "主人" elevates the meaning from a simple "owner" to the "leading figure" or "protagonist," a term now used primarily in literary and social contexts to denote the central character of a story or the primary individual in an event.