'映射' (yìng shè) literally combines '映' (to reflect, to shine upon) and '射' (to shoot, to project), evoking the image of light bouncing off a surface or an idea being cast onto another domain. Figuratively, it means to reflect or represent something abstractly — such as how emotions, social trends, or cultural values are mirrored in literature or behavior. It implies a non-literal, often one-to-one correspondence between two systems or ideas.

In technical contexts — especially mathematics, computer science, and linguistics — '映射' is the standard term for 'mapping': a precise relationship where each element from one set corresponds to exactly one element in another set (e.g., function mapping, memory mapping, or phonetic mapping). Unlike casual synonyms like '反映', '映射' carries formal, structural connotations and is rarely used in everyday speech without technical or analytical intent.