The Chinese word **急诊 (jízhěn)**, meaning "emergency treatment" or "emergency room," is a compound noun formed through semantic combination. It consists of two characters: **急 (jí)**, which means "urgent" or "rapid," and **诊 (zhěn)**, which means "to diagnose" or "to treat." When combined, the modifier **急** describes the nature of the **诊**, specifying that it is urgent medical care. This formation follows a common modifier-head structure in Chinese, where the first character qualifies the second, resulting in a precise term for immediate medical attention typically provided by a hospital's emergency department.