The word **秋千** (qiūqiān), meaning "swing," is a classic example of a disyllabic compound formed through the **rebus principle**, where characters are borrowed purely for their sound to represent a foreign word. It originates from an ancient Altaic term for a swing or trapeze, transcribed phonetically into Chinese as **秋千**. The characters 秋 (autumn) and 千 (thousand) bear no semantic relation to the object; they were chosen solely for their phonetic approximation. Later, the signific (radical) **革** (leather) was sometimes added to create **鞦韆**, to visually associate the word with leather swing ropes, but the simplified form **秋千** remains standard. Thus, its formation is primarily phonetic borrowing with subsequent occasional semantic clarification.