insulator

noun

in·​su·​la·​tor ˈin(t)-sə-ˌlā-tər 

: 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

Examples of insulator in a Sentence

Metal is not a good insulator.

Recent Examples on the Web

Kent Nishimura / Los Angeles Times via Getty Images The 73-acre plot is bordered by a dense green forest, which serves as an effective insulator from the hustle and bustle of nearby Massachusetts Avenue. —Mary Cunningham, CBS News, 1 Oct. 2024

The process happens because quartz is an insulator, and gold is a conductor. —Elizabeth Gamillo, Smithsonian Magazine, 9 Sep. 2024

Add in a rigid body, damping silicon insulators, as well as a tonearm with high-initial motion sensitivity, and playback should be smooth and precise. —Bryan Hood, Robb Report, 9 Sep. 2024

The key seems to be that quartz is an insulator, while gold is famously a great conductor of electricity. —Michael Irving, New Atlas, 2 Sep. 2024

Word History

First Known Use

1801, in the meaning defined above

Kids Definition

insulator

noun

in·​su·​la·​tor ˈin(t)-sə-ˌlāt-ər 

: one that insulates

especially : a material that is a poor conductor of heat or electricity or a device made of such material

Medical Definition

insulator

noun

in·​su·​la·​tor ˈin(t)-sə-ˌlāt-ər 

: a material that is used to provide insulation

also : a device made of such material