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

But illegitimate examples had thinner insulators or none at all, and little or no safety tape. —Andrew Moseman, IEEE Spectrum, 22 Nov. 2025

While many insulators excel only in specific conditions, the Mia performed equally well on mild ski tours and frigid, windy lift rides. —Jenny Wiegand, Outside, 19 Nov. 2025

Until recently, scientists could consistently produce nanotubes from carbon—capable of acting as semiconductors or semimetals—and from boron nitride, an insulator. —Jijo Malayil, Interesting Engineering, 9 Nov. 2025

In areas with heavy winter snowpacks, the snow acts as a great insulator, protecting the underground portions of the plant. —Andy Wilcox, Better Homes & Gardens, 9 Nov. 2025

Word History

First Known Use

1801, in the meaning defined above

Rhymes for insulator

• activator
• actuator
• agitator
• alligator
• allocator
• alternator
• animator
• annotator
• applicator
• arbitrator
• aspirator
• aviator

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