1. Very uncertain
   "left everything up in the air" 
2. Not yet determined
   "plans are still up in the air"

See also: uncertain

• fungibility
• fungible
• fungicidal
• fungicide
• fungiform
• fungoid
• fungous
• fungus
• fungus family
• fungus genus
• fungus gnat
• fungus kingdom
• fungus order
• funguslike
• funicle
• funicular
• funicular railway
• funiculitis
• funiculus
• funk
• funk hole
• funk music
• Funka
• Funkaceae
• funky