Collins COBUILD Advanced Learner's English Dictionary - rarefied

1. If you talk about the rarefied atmosphere of a place or institution, you are expressing your disapproval of it, because it has a special social or academic status that makes it very different from ordinary life. It is important for the state’s future administrators to get out of the rarefied air of the capital. ADJ: usu ADJ n c darkgreen]disapproval 2. Rarefied air is air that does not contain much oxygen, for example in mountain areas. ...living at very high altitudes where the atmosphere is rarefied. ADJ