fly-up I. \ˈ ̷ ̷ˌ ̷ ̷\adjective 1.: arranged to open by flying upward < a fly-up lid > 2.: arranged to be reached by flying < the advantages of fly-up waterers in the poultry house > II. noun (-s) : a ceremony at which a brownie scout formally leaves her brownie troop and becomes a member of an intermediate girl scout troop