清醒 (qīng xǐng) is an adjective meaning 'clear-headed' or 'sober', describing a mental state in which one’s thinking is sharp, alert, and unimpaired by fatigue, alcohol, drugs, or confusion. The first character 清 (qīng) means 'clear', 'pure', or 'unclouded', while the second character 醒 (xǐng) means 'to wake up' or 'to become aware'. Together, they convey the idea of being fully awake and mentally lucid — not just physically awake, but cognitively present and perceptive.

This word is commonly used in health-related contexts (e.g., recovering from illness, intoxication, or anesthesia), psychological discussions, or situations requiring sound judgment. It often appears in formal or written Chinese — such as medical reports, news articles about accidents, or advice on safe driving — and carries a slightly elevated register compared to everyday alternatives like 醒着 (xǐng zhe, 'awake'). It can also be used metaphorically, as in '清醒地面对现实' ('face reality clearly and realistically').