Dielectric
DIELECTRIC, in electricity, a non-conductor of electricity; it is the same as insulator. The "dielectric constant" of a medium is its specific inductive capacity, and on the electromagnetic theory of light it equals the square of its refractive index for light of infinite wave length (see Electrostatics; Magneto-Optics).
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)
