|lightning conductor or lightning rod|
|a metal strip terminating in a series of sharp points, attached to the highest part of a building, etc, to discharge the electric field before it can reach a dangerous level and cause a lightning strike|
|lightning rod or lightning rod|
metallic rod (usually copper) that protects a structure from lightning damage by intercepting flashes and guiding their currents into the ground. Because lightning tends to strike the highest object in the vicinity, rods are typically placed at the apex of a structure and along its ridges; they are connected to the ground by low-impedance cables. In the case of a building, the soil is used as the ground; on a ship, the water is used.
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