plumb bob

• Objet lourd et pointu, généralement en métal, attaché à une corde ou à un fil, utilisé pour déterminer la verticale exacte, la profondeur ou l'alignement, notamment dans la construction, la topographie ou la maçonnerie.

A pointed weight attached to a line, used to determine vertical alignment or depth, especially in construction, surveying, or masonry.

1. Weighted tool for vertical alignmentC1formal

   A pointed weight attached to a string, used to establish a true vertical line (a plumb line) in construction and surveying.

   fil à plomb

   • The carpenter used a plumb bob to ensure the wall was perfectly straight.
   • Surveyors rely on a plumb bob for accurate vertical measurements.
   • He dropped the plumb bob from the top of the structure to check its alignment.