The word 住院 (zhùyuàn) is formed through a direct and vivid spatial metaphor. It combines the character 住 (zhù), meaning "to reside" or "to stay", with 院 (yuàn), meaning "courtyard" or "enclosed institution". Together, they create the concept of "residing within the courtyard", where the "courtyard" specifically implies a hospital or clinic compound. Thus, the term literally paints a picture of a patient entering and remaining inside the physical confines of a medical institution to receive care, capturing the entire experience of being formally admitted for treatment.