bumpy (adj.) Look up bumpy at Dictionary.com
of a road, etc., "marked by bumps," 1865, from bump + -y (2). Of airplane flights, "uneven because of bumps," 1911.
Fasten your seatbelts. It's going to be a bumpy night. [Bette Davis ("Margo Channing"), "All About Eve," 1950]
Related: Bumpiness.