The word 码头 is formed by combining two characters: 马 (mǎ), meaning "horse", and 头 (tóu), meaning "head". Historically, at docks and ports where boats would moor, horses and carts were the primary means for loading and unloading cargo. The area at the very front or end of the wharf, where this vital transfer between water and land transport occurred, became metaphorically known as the "horse's head", the crucial point of activity. Thus, the term evolved to represent the pier or dock itself, encapsulating its function as the bustling interface for trade and transport.