overscan 
Geek box term. The amount of picture area that gets cropped off along the edges of a television screen. Zero percent overscan means the television does not crop off any of the incoming picture. Overscan is often set intentionally at the factory to be 5 percent, or even higher along the edges, to ensure the screen is full at all times regardless of fluctuations in brightness (which can change the overall picture size) or nonstandard signals, such as those from camcorders or video games.