The word 枪手 is formed through a vivid metaphorical process, combining the character for "gun" (枪) with the character for "hand" (手). It originates from the literal image of a person who wields a firearm, such as a soldier or sharpshooter. This concrete concept is then extended metaphorically to describe a person who acts as a substitute, particularly in exams or writing, where they "fire" or "shoot" answers or text on behalf of someone else, wielding a pen or keyboard as their modern "gun". The term thus captures the essence of a hired agent performing a targeted task with skill and for another's benefit.