What is the Abbreviation for Air Conditioning?

A.C. is most commonly used as a term for Air Conditioning. As many films and television series demonstrate with one phrase, usually being shouted in a frustrated tone "Turn on the A.C.", refering to the desire to cool down an otherwise hot room.

It could also stand for "Alternating Current" which is a term used in electronics, commonly with "Direct Current" as in an AC/DC power adapter.