noun

• (informal) An action or stunt where a bicycle, motorcycle, or other vehicle is ridden for a short period while it is standing only on its rear wheel or wheels.
  "Jim fell off his bike when he was trying to do a wheelie."
• (informal, chiefly Australia) A wheelchair user.
  "It is also a nightmare for the wheelies, or wheelchair users. Not only is it hard enough to find a bloody wheelchair in the airport these days, but to push them to this back-of-beyond gate is a job in itself."

verb

• (intransitive, informal) To ride, or perform the stunt of riding, a vehicle on its rear wheel or wheels.
  "Downshift while the engine is still revving well. This will prevent missed gears when you stomp the shift lever in a panic to regain power. Also, if you wait too long to shift down, you risk the possibility of wheelieing when you catch the next lower cog. A wheelie will cause you to shut off for a second … and it's all over brother. Go back down and try again."

adj

• (informal) Alternative spelling of wheely (“having wheels; mounted on wheels”).
  "wheelie bag  wheelie bin"