water bike

Short definition from Wiktionary

Noun

1. 1
   Abbreviation of water bicycle.
2. 2
   Synonym of aqua bike.
3. 3
   Alternative form of waterbike.
4. 4
   A hydrofoil bike; a bicycle frame with the rear wheel replaced by a lift hydrofoil and propeller, and the front wheel replaced by a rudder, lift hydrofoil and elevator hydrofoil