dielectric vs insulator

dielectric and insulator both are nouns.

Word	Noun	Adjective	Verb	Adverb
dielectric	Yes	No	No	No
insulator	Yes	No	No	No

As nouns, dielectric and insulator are synonyms defined as:

dielectric and insulator: a material such as glass or porcelain with negligible electrical or thermal conductivity

Other synonyms of dielectric include nonconductor.

dielectric (noun)	insulator (noun)
a material such as glass or porcelain with negligible electrical or thermal conductivity	a material such as glass or porcelain with negligible electrical or thermal conductivity