WordNet (r) 3.0 (2006):

air conditioning
    n 1: a system that keeps air cool and dry [syn: air
         conditioner, air conditioning]

Moby Thesaurus II by Grady Ward, 1.0:

36 Moby Thesaurus words for "air conditioning":
   adiabatic absorption, adiabatic demagnetization,
   adiabatic expansion, aerage, aeration, air cooling, airing,
   blast freezing, chilling, congealment, congelation, cooling,
   cross-ventilation, cryogenics, deep freezing, dehydrofreezing,
   electric refrigeration, food freezing, freezing, gas refrigeration,
   glaciation, glacification, infrigidation, mechanical refrigeration,
   oxygenation, oxygenization, perflation, quick freezing,
   reduction of temperature, refreezing, refreshment, refrigeration,
   regelation, sharp freezing, super-cooling, ventilation