Definition - What does Dead Pixel mean?
Techopedia explains Dead Pixel
A dead pixel is often incorrectly used as a synonym for stuck pixels, which are pixels simply stuck either in the on or in the off state, mostly because they usually have the same appearance. But as a constant, a dead pixel is always off, whereas some stuck pixels can be either off or on, and popular solutions found on the Web can sometimes help in recovering stuck pixels. Another distinction is that all the sub-pixels in a dead pixel are dead as opposed to stuck pixels, which usually have one or two sub-pixels stuck in one state or the other. Dead pixels are becoming increasingly difficult to notice as the resolutions of LCD screens go up and the sizes of individual pixels go down.