Overspray refers to the application of any form of paint

Paint

Paint is any liquid, liquefiable, or mastic composition which after application to a substrate in a thin layer is converted to an opaque solid film. One may also consider the digital mimicry thereof...

, varnish

Varnish

Varnish is a transparent, hard, protective finish or film primarily used in wood finishing but also for other materials. Varnish is traditionally a combination of a drying oil, a resin, and a thinner or solvent. Varnish finishes are usually glossy but may be designed to produce satin or semi-gloss...

, stain

Stain

A stain is a discoloration that can be clearly distinguished from the surface, material, or medium it is found upon. Stains are caused by the chemical or physical interaction of two dissimilar materials...

 or other non-water soluble airborne particulate material onto an unintended location. This concept is most commonly encountered in graffiti

Graffiti

Graffiti is the name for images or lettering scratched, scrawled, painted or marked in any manner on property....

, auto detailing, and when commercial paint jobs drift onto unintended objects.

Auto detailing and drifting paint

Overspray is considered a negative occurrence in auto detailing or when drifting paint gets on cars, buildings, etc. during the painting of a water tower, bridge or industrial buildings. There are businesses created solely to clean overspray off surfaces...there are many potential
ways to clean oversprayed cars: solvents, razor blades, rubbing compounds. But the most common procedure to remove overspray is the use of a specialty clay bar. There are many manufacturers of such bars, including: meguiars, 3M, clay magic, mothers. There are an estimated 200,000 oversprayed cars per year in the United States.