铅垂线 qiānchuíxiàn plumb line; sounding line; lead line Definitions Defs Origin Strokes Stroke Words Sentences Sents 铅 鉛 qiān noun lead lead (chemical element, Pb)垂线 垂線 chuíxiàn perpendicular line a line that is perpendicular or vertical to another line or plane; often used in mathematics
