Plumb-line
Pronunciation: /ˈpɫəm- ˈɫaɪn/
Plumb-line (noun)
- A thin string with a heavy weight at one end, used to show the true vertical direction.
- The straight line in the direction of gravity, used as a reference for checking alignment.
Examples
- The plumb-line hangs straight from the ceiling.
- A plumb-line helps check if a wall is truly vertical.