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

See also: uncertain

• hula
• hula-hoop
• hula-hula
• Huldreich Zwingli
• hulk
• hulking
• hulky
• hull
• hullaballoo
• hullabaloo
• huller
• hullo
• Hulsea
• Hulsea algida
• Hulsea nana
• hum
• human
• human action
• human activity
• human being
• human beings
• human body
• human botfly
• human chorionic gonadotrophin
• human chorionic gonadotropin