1. [adj]  very uncertain; "left everything up in the air"
2. [adj]  not yet determined; "plans are still up in the air"

Up in the Air
Ryan Bingham`s somewhat bizarre goal is to accumulate a million miles in his frequent flyer account. His life in the air--and specifically the last leg of his world-wide itinerary--is the subject of this very 21st-century novel, in which Ryan is firmly connected to the earth via phone and computer even as he soars above it. A New York Times Notable Book for 2001.

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