#plumb_line__plumbline__perpendicular  a cord from which a metal weight is suspended pointing directly to the earth's center of gravity; used to determine the vertical from a given point
  supertype:  cord  a line made of twisted fibers or threads; "the bundle was tied with a cord"
  part:  plumb_bob
  subtype:  lead_line__sounding_line  (nautical) plumb line for determining depth
  subtype:  plumb_rule__plumbrule  a plumb line attached to a narrow board

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