From Longman Dictionary of Contemporary Englishbe up in the airbe up in the airif something is up in the air, no decision has been made about it yet Our trip is still very much up in the air. → air
Examples from the Corpus
be up in the air• They still haven't said if I've got the job -- it's all up in the air at the moment.• If I don't work to a routine then I feel everything is up in the air!• When he was up in the air he was engaged, his spirits prospered and his intellect was keener than a needle.• I might be going on a training course next week, but it's still up in the air.• Our trip to Orlando is still up in the air.• But they were up in the air, and they were moving.• It was wonderful to be up in the air and to feel the air swishing past his face. 