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Glite Dictionary
plumb line

plumb line

1 5.3
A string with a metal weight that shows a straight up-and-down line
  • noun
  • /plʌm laɪn/
  • Specialized
translation icon : línea de plomada
  • The carpenter used a plumb line to check if the post was standing straight.
  • dropping a plumb line
  • straight as a plumb line
  • used a plumb line

Relations of force fluid, the dip of the Plumb line, the pull of eyes.

Examples

  • Keep the plumb line vertical...

    Fiction book (1992)

  • You would need a plumb line to know which way is up, exactly.

    Blog text (11)

  • The base of the neck at the front should be exactly on the Plumb line and then the rest follows like this.

  • You want a plumb line to run from your ear through your hips to your feet.

    Without Limits (1998)

  • And so a Plumb line is how you tell if something's straight.

  • A freely swinging plumb line is suspended from the center of the protractor.

    Academic text (1991)

  • The most advanced task, that of ensuring that the lines of the building are perfectly vertical, rests in the hands of the bearded master, who dangles a plumb line.

    Academic text (2008)

  • He used a plumb line to check his apparatus, and he devised a movable pointer to help locate Mercury on the Sun's disk.

    Academic text (2006)

  • To ensure the wall is perfectly vertical, drop a plumb line from the top to measure its alignment.

  • For accurate results, lower the plumb line to see the true vertical line against the structure.

Synonyms

plumb rule
vsplumb line
  • Specialized
7.9

A straight narrow board with a hanging weight used to check if a wall is perfectly vertical

has only a suspended weight and cord without a rigid guide for vertical check
plumb level
vsplumb line
  • Specialized
7.2

A tool with a hanging string and a bubble level to check vertical or horizontal lines

is only a hanging weight and cord used just to show vertical direction

How Accurate

plumb line
  • Specialized
1 5.3
plumb rule
  • Specialized
7.9
level
  • Specialized
145 3.2

Surface Forms

plumb line singular
plumb lines plural

Morphology

plumb + line

The meaning is directly compositional: 'plumb' (a weighted bob used to mark vertical alignment) combined with 'line' (a cord) yields a cord with a plumb used to find vertical. This is a literal noun–noun compound that follows common descriptive compounding patterns (and has clear cross-linguistic equivalents), so a B1 learner who knows both constituents would readily infer the MWE meaning.

Etymology

The noun plumb line comes from a simple tool: a plumb, a heavy 'lead' weight, hung on a line. When the weight hangs still it shows the true 'up-and-down' direction, so a plumb line is used to check that walls or pictures are perfectly straight.