What is rear demister?

Answer 1

I would believe a demister is actually commonly know as a rear defogger. A long coil that loops the rear window that heats up to remove condensation caused by the interior of the car being colder than the temperature outside the car. Think of it this way: A glass filled with ice-water will have moisture on the outside of the glass. Imagine if you warmed the glass to the same temperature or higher than the air around it, the moisture would evaporate. The rear demister works in the same way. The lines going across your rear window is actually a single thin piece of metal with wires attached on either end. When electricity is applied, the metal heats up warming the window.