#insulator__dielectric__nonconductor  a material such as glass or porcelain with negligible electrical or thermal conductivity
  exclusion:  conductor.material
  supertype:  material.substance__stuff  the tangible substance that goes into the makeup of a physical object; "coal is a hard black material"; "wheat is the stuff they use to make bread"
  subtype:  bushing  an insulating liner in an opening through which conductors pass
  subtype:  mineral_wool__mineralwool__rock_wool  a light fibrous material used as an insulator
  subtype:  glass_wool__glasswool  glass fibers spun and massed into bundles resembling wool

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