The word **胶卷** (*jiāojuǎn*, meaning "photographic film") is a compound noun formed through semantic combination: the first character **胶** (*jiāo*) means "glue" or "gelatin," referring to the light-sensitive emulsion layer made of gelatin and silver halides coated on the base, while the second character **卷** (*juǎn*) means "roll" or "coil," describing the physical form in which the film is stored and advanced in cameras. Thus, the term literally and logically denotes a "gelatinous roll," accurately capturing both the material composition and the physical structure of traditional photographic film.