aircon
n.— «Then came air conditioning, also known as aircon. This uses an air-conditioner to chill (and dehumidify) the air coming into the cabin. The end result is that when it’s turned on, and the temperature gauge is set to cold, you get air into the car which is actually cooler than the outside air.» —“Jargon Buster” by Joe Toner Galway First (Ireland) Apr. 30, 2007. (source: Double-Tongued Dictionary)
Further reading
The slang term 4-55 air conditioning is means cooling a car by driving fast with all the windows down. This is part of a complete episode.
Related
A young listener wonders: Why do the words icing and frosting both refer to the idea of being cold? The names for this sweet cover on a cake refer to its appearance, not its temperature. Something similar occurs with the glaze in glazed doughnut...