lapper

Lapper is a noun derived from lap, with several senses in English. In sports, a lapper commonly refers to a competitor who has completed one or more additional laps relative to others, effectively lapping the field. In race reports and commentary, the term is used informally to describe a car or rider that is “a lap ahead” of backmarkers, producing lapped traffic that must be handled according to race rules and safety practices.

In motorsport, lapping can influence race dynamics by creating opportunities for overtaking, traffic management, and strategic decisions. Lapped cars are typically allowed to complete the race but must avoid obstructing faster cars; the exact rules vary by series.

In manufacturing and engineering, a lapper is a machine or operator involved in lapping, a precision finishing process. Lapping uses abrasive materials to remove tiny amounts of material and to produce very smooth, flat surfaces. It is employed to achieve tight dimensional tolerances and high surface quality on components such as bearings, gears, optical elements, and gauge surfaces. Lapping methods include slurry lapping, which uses an abrasive suspension, and diamond lapping, which relies on diamond abrasives. Lapping can be performed on manual setups or automated equipment, depending on the required precision and production scale.

The term also appears as a general descriptor for something that laps or overlaps, though this usage is less common. Overall, lapper captures two primary contexts—sports terminology for a competitor who laps others, and industrial terminology for a finishing process and the equipment that performs it.