demister

plural demisters

1. The part of the ventilation system in a motor car that blows hot, dry air against the inside of the windscreen to prevent or remove condensation.

   These screens incorporate a layer of transparent gold film in the laminations which forms an electric heating element to act as de-icer and de-mister.

   1960 February 28, “High-Voltage Electric Locomotive for British Railways”, in Railway Magazine, page 125

   1 more example

   The drivers' cabs are fitted with the latest equipment, including a loudaphone, electric demisters and two-tone horns; provision is made for the fitting of A.W.S. equipment when available.

   1962 December, “The Oxted Line diesel-electric multiple-units”, in Modern Railways, page 383

   Synonyms: defogger, defroster

2. Any of various devices that remove droplets of water from air.