The Collaborative International Dictionary of English v.0.48:

airborne \airborne\ adj.
   1. conveyed by or through air, as dust or pollen; as, a clean
      room is needed to avoid airborne contaminants.
      [WordNet 1.5]

   2. in flight; flying; -- said of an airplane.
      [PJC]

   3. (Mil.) carried directly to the site of battle by aircraft;
      -- said of combat troops, as, an airborne division.
      [PJC]

WordNet (r) 3.0 (2006):

airborne
    adj 1: moved or conveyed by or through air