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insulator

noun in·su·la·tor \ ˈin(t)-sə-ˌlā-tər \
|Updated on: 14 Aug 2018

Definition of insulator

: one that insulates: such as
a : a material that is a poor conductor (as of electricity or heat) — compare semiconductor
b : a device made of an electrical insulating material and used for separating or supporting conductors

See insulator defined for English-language learners

See insulator defined for kids

Examples of insulator in a Sentence

  1. Metal is not a good insulator.

Recent Examples of insulator from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'insulator.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of insulator

1801

in the meaning defined above

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INSULATOR Defined for English Language Learners

insulator

noun

Definition of insulator for English Language Learners

  • : a material that allows little or no heat, electricity, or sound to go into or out of something

INSULATOR Defined for Kids

insulator

noun in·su·la·tor \ ˈin-sə-ˌlā-tər \

Definition of insulator for Students

: a material (as rubber or glass) that is a poor conductor of electricity, heat, or sound

Medical Dictionary

insulator

noun in·su·la·tor \ ˈin(t)-sə-ˌlāt-ər \

medical Definition of insulator

: a material that is used to provide insulation; also : a device made of such material

Learn More about insulator

  1. See words that rhyme with insulator Spanish Central: Translation of insulator Nglish: Translation of insulator for Spanish speakers Britannica English: Translation of insulator for Arabic speakers Britannica.com: Encyclopedia article about insulator

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