plumb line

noun

1. a cord with a lead bob attached to one end, used to determine perpendicularity, the depth of water, etc.

2. plumb rule.

plumb line

noun

1. a string with a metal weight at one end that, when suspended, points directly towards the earth's centre of gravity and so is used to determine verticality, the depth of water, etc

2. another name for plumb rule

plumb line

1. A line regarded as directed exactly toward the Earth's center of gravity.

Word History and Origins

Origin of plumb line¹

First recorded in 1530–40

Example Sentences

"It's the lead weight from a plumb line."

Read more on BBC

Drop a plumb line from the top of the head down through the spine into the heels in first position, divide the body down this center, right from left.

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“When I took down the remaining wallpaper in preparation for new wallpaper, I came across all her notes, measurements and marks for plumb lines. It brought back so many memories.”

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The referee goes to or near the spot where the ball was punted and watches its flight, drawing an imaginary plumb line between that point and where the ball intersects the sideline.

Read more on Los Angeles Times

Then, using a level in the vertical position, draw a straight vertical line on the wall in pencil; this is called a “plumb line.”

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