The word **时差 (shíchā)**, meaning "time difference," is a classic example of a Chinese compound word formed through semantic combination, where two meaningful characters—**时 (shí)**, meaning "time," and **差 (chā)**, meaning "difference" or "discrepancy"—are joined to create a new, specific term that logically represents the gap in clock time between different geographic time zones. This method of formation, known as *modifier-head* or *coordinative* compounding, is highly productive in Chinese, allowing for clear and efficient creation of vocabulary by combining existing conceptual building blocks.