The word 主角 is formed by combining two characters to create a new, unified concept. The first character, 主 (zhǔ), carries the core meaning of "primary", "main", or "master". It is paired with 角 (jué), which in this context departs from its literal meaning of "horn" to represent the idea of a "role" or "part" in a performance. The formation is a direct and elegant conceptual fusion: the "primary role", visually and semantically marrying the notion of centrality with theatrical function to specifically denote the leading character in a story or drama.