Controlled maneuver where rider and surfboard briefly lift off the water while dropping into a steep or concave wave face. The air-drop is usually done right after the surfer gets to his feet and begins riding.
For decades, surfers sometimes mistakenly went airborne on takeoff, almost always resulting in a wipeout. Not until the late '80s was it discovered that by shifting the weight to the back foot while remaining centered and low over the board, the surfer could improve his chances of making a steep drop by intentionally going airborne. Skateboarding helped show the way, as skaters, years earlier, had figured out how to drop into vertical terrain from a cold start.