‘Lái lóng qù mài’ literally means ‘the coming dragon and departing pulse’—a vivid metaphor rooted in traditional Chinese geomancy (feng shui), where ‘dragon’ symbolizes the winding, energetic flow of mountains and rivers, and ‘pulse’ represents the subtle, life-sustaining channels of energy. Over time, the phrase evolved into a fixed idiom meaning the full origin, development, and underlying logic of something—like tracing the entire ‘life story’ of an event, idea, or problem.

It’s commonly used in formal writing, academic discussions, news analysis, and thoughtful conversation when explaining complex situations. While the characters ‘dragon’ and ‘pulse’ evoke imagery from nature and medicine, the idiom itself is abstract and rarely refers to literal animals or anatomy. Native speakers use it to signal that they’re about to give—or request—a thorough, chronological account, not just surface facts.