plumb line
英 [ˈplʌm laɪn]
美 [ˈplʌm laɪn]
n. (测水深或垂直面用的)重锤线，铅垂线
牛津词典
noun
- （测水深或垂直面用的）重锤线，铅垂线
a piece of thick string with a weight attached to one end, used to find the depth of water or to test whether a wall, etc. is straight
柯林斯词典
- （检查垂直度的）铅垂线
Aplumb lineis a piece of string with a weight attached to the end that is used to check that something such as a wall is vertical or that it slopes at the correct angle.
英英释义
noun
- a cord from which a metal weight is suspended pointing directly to the earth's center of gravity