non-conductor

non-conductor — noun

1. a material that strongly blocks the flow of thermal energy, electrical current,

1.nounB2
Definition

a material that strongly blocks the flow of thermal energy, electrical current, and sound waves, allowing almost nothing to travel through it

Example

Romi used rubber gloves as a non-conductor when fixing the electrical wires at home.

non-conductor used as a protective material

The physics team tested whether the new ceramic material was a good non-conductor of sound.

non-conductor + of + [sound] pattern

Common collocations
  • non-conductor of heat
  • non-conductor of electricity
  • non-conductor of sound
  • good non-conductor
  • excellent non-conductor
  • perfect non-conductor
  • act as a non-conductor
  • use as a non-conductor
Synonyms
  • insulator

    much more common in everyday use; covers both electrical and thermal contexts

  • dielectric

    technical term restricted to electrical non-conductors in physics and engineering

Antonyms
  • conductor

    a substance that allows heat, electricity, or sound to pass through easily

Grammar Patterns

non-conductor + of + [heat/electricity/sound]

Usage Note

Often used with the preposition 'of' to specify which form of energy cannot pass through (e.g., non-conductor of heat, non-conductor of electricity). The more common everyday term is 'insulator'.

Word family

Synonym discussion

Sense: noun/1

Non-conductor, insulator, and dielectric all describe materials that resist the flow of energy, but they differ in scope and setting. Insulator is by far the most common word in everyday English — people talk about insulating their homes or wires being insulated. Non-conductor is more literal and technical, often appearing in physics textbooks or lab reports when describing a substance's specific property. Dielectric is the narrowest of the three: it is used only for electrical non-conductors in engineering contexts, especially capacitors and circuit boards. For example: 'Rubber is an excellent electrical insulator' (everyday), 'Rubber acts as a non-conductor of electricity' (more formal), and 'The dielectric layer prevents short circuits in the capacitor' (technical only).

non-conductor ↗insulator ↗dielectric ↗

Common collocations

Nouns

Phrases

  • act as a non-conductor
  • use as a non-conductor

Prepositions

  • of (non-conductor of heat)

Etymology

LatinOld FrenchEnglish

Formed by combining the prefix non- ('not') with conductor ('a substance that directs or transmits energy'). The prefix non- comes from Latin non meaning 'not', while conductor traces through Old French and Latin conducere ('to lead together, to bring together'). The term non-conductor first appeared in English scientific writing in the 18th century, during the early experimental study of electricity.

First known use

1751

1751, in the meaning defined above