Use of a plumb bob a level used on plumb rather then horizontal
Use a plumb line.
To show a vertical line
The plumb line is a vertical straight line.
A plumb bob is a weighted instrument used in construction and carpentry to create a vertical reference line. It helps ensure that structures are built accurately and in alignment with a true vertical.
The plumb bob is useful in establishing vertical for a wall in construction or a doorjamb when hanging a door. It can indicate whether a flue is running true vertical or veering off plumb. A plumb-bob or a plummet is a weight, usually with a pointed tip on the bottom, that is suspended from a string and used as a vertical reference line, or plumb-line. It is essentially the vertical equivalent of a water level.
A line 90 degrees from horizontal is a plumb line.
In a vertical or perpendicular line. e.g. "The wall is plumb."This is the most common meaning and alludes to the method of establishing vertical by using a plumb bob - a weight suspended from a long line which hangs straight down - with the resulting line between the top of the line and the plumb bob being a reference for the edge of something that is supposed to be perfectly vertical. If it is further away from the line at the top or bottom of the line than it is at the other end, it is not quite "plumb".There are, of course, several more informal uses for the term:(Informal definition) Directly; squarely: e.g. "It fell plumb in the middle."(sometimes also spelled as "plum" with the informal definition...) Utterly; completely: e.g "I'm plumb worn out."informal chiefly US (intensifier): e.g. "That's just plumb stupid."
In a vertical or perpendicular line. e.g. "The wall is plumb."This is the most common meaning and alludes to the method of establishing vertical by using a plumb bob - a weight suspended from a long line which hangs straight down - with the resulting line between the top of the line and the plumb bob being a reference for the edge of something that is supposed to be perfectly vertical. If it is further away from the line at the top or bottom of the line than it is at the other end, it is not quite "plumb".There are, of course, several more informal uses for the term:(Informal definition) Directly; squarely: e.g. "It fell plumb in the middle."(sometimes also spelled as "plum" with the informal definition...) Utterly; completely: e.g "I'm plumb worn out."informal chiefly US (intensifier): e.g. "That's just plumb stupid."
Mainly bricklayers, but also anyone else that need to know if something is perfectly vertical in all planes (from all directions).
The homonym of "plum" is "plumb," which refers to a weight on the end of a line to measure water depth or a tool used for finding the vertical in construction.
II Samuel 8:2 is the account that you are referring to, but the mention of a plumb-line is not in this passage. The only passage in scripture that mentions a plumb-line is in Amos 7:7-8. A plumb-line is used for vertical alignment. David used a chord , or rope as a measuring tool to separate out a third to one half of the Moabites.
Plumb line testThis is a quick visual check to see if the spine is straight. In scoliosis, the plumb line will fall to the left or right of the spine instead of through the middle of the buttocks. Plumb line dropped from the prominent vertebra of C7 (vertebra prominence) measures the decompensation of the thorax over the pelvis. The distance from the vertical plumb line to the gluteal cleft is measured in centimeter and is recorded along with the direction of deviation. If there is cervical or cervico-thoracic curve, the plumb should fall from the occipital protuberance (inion).