Other forms: bumpier; bumpily; bumpiest
Bumpy means not smooth, as in covered in lumps and bumps, like a bumpy path that makes your car bounce, or a bumpy road to getting your parents to lend you the car.
Anything covered in bumps is bumpy, whether it’s a road, the skin of a toad, or the surface of the birthday cake you made for your brother. It can also describe a ride full of unexpected jolts and bumps: "It was a bumpy journey along the mountain passes in her Jeep." Figuratively, bumpy can also describe a difficult process: "What a bumpy ride that was, getting my visa to travel to China!"