if a matter is up in the air, no decision has been made, often because other matters have to be decided first.

I may be moving to New Zealand, but it's still up in the air.

• bottom drops out of the market
• bottom falls out of the market
• bottom fell out
• bottom fell out of
• bottom fell out of something
• bottomless pit
• bottom line
• bottom of the barrel
• bottom of the heap
• bottom of the hour
• bottom of the ladder
• bottom out
• bounce back
• bounce back from
• bounce back from something
• bound and determined
• bound up in
• bound up in something
• bound up with
• bound up with something
• bow and scrape
• bow down
• bow down to
• bow down to someone
• bow down to something