Nonconductor

Part of speech: noun

Definitions

1. A material that restricts the flow of electric current and heat energy
2. A substance that does not allow electricity or heat to pass through it easily
3. A type of material that hinders the transmission of electric current and thermal energy

Etymology: The surprising part here is how little there is to surprise. "Nonconductor" is a plain English compound: the prefix "non-" attached to "conductor," so it means something that is not a conductor. Its first half traces back a long way, to a Proto-Indo-European root for "not" that passed through Proto-Germanic and Old English as "nān," meaning "not one" or "none," and eventually softened into the prefix "non-" that English uses freely today. The second half carries the real meaning. "Conductor" comes from the Latin verb "conducere," meaning to lead or bring together, and in physics it came to describe a substance that lets electricity flow through it. A nonconductor is the reverse: a material that resists that flow, such as rubber, glass, or dry wood, and that is why insulators are often described with this word. Put together, the word is a transparent piece of modern technical vocabulary, built from an ancient negative prefix and a Latin-derived term. Its meaning is exactly what the parts say, which is why it reads so clearly.