nonconductor

/ˌnɑnkənˈdʌktər/
noun
  1. A material or substance that does not readily transmit heat, electricity, or sound; an insulator.
    • Wood is a natural nonconductor of heat, which is why wooden spoons are used for cooking.
    • Rubber is a nonconductor of electricity, making it perfect for protective gear.
    • Air is a nonconductor of sound in a vacuum, but it conducts sound under normal conditions.
Antonyms