The word 表情 is formed by combining two characters: 表, which conveys the idea of "to show" or "to express" (like the surface of something that is visible), and 情, which means "feelings", "emotions", or "situation". Conceptually, it is a direct and logical compound where the first element (表) acts upon the second (情), creating the core meaning of "expressing one's feelings". This is most concretely and commonly understood as the expression shown on one's face, where inner emotions become outwardly visible. Thus, the formation visually and notionally represents the act of making internal emotions manifest on an external surface.